UNIVERSITY OF CALIFORNIA 
 
 COLLEGE OF AGRICULTURE 
 
 AGRICULTURAL EXPERIMENT STATION 
 
 BERKELEY, CALIFORNIA 
 
 BIOLOGY AND CONTROL OF 
 
 AVOCADO INSECTS 
 
 AND MITES 
 
 HOWARD L. MCKENZIE 
 
 BULLETIN 592 
 
 JULY, 1935 
 
 UNIVERSITY OF CALIFORNIA 
 BERKELEY, CALIFORNIA 
 
CONTENTS 
 
 PAGE 
 
 Introduction 3 
 
 Key to diaspine scales attacking 
 
 the avocado in California . . 4 
 
 Latania scale 6 
 
 History and synonomy ... 7 
 
 Distribution and hosts ... 7 
 
 Life history ....... 8 
 
 Parasites and predators ... 10 
 
 Control 10 
 
 Dictyospermum scale .... 15 
 
 Greedy scale 15 
 
 Ivy or oleander scale 15 
 
 Red scale 15 
 
 Soft brown scale 16 
 
 Black scale . . . . . .16 
 
 Omnivorous looper 16 
 
 History and synonomy ... 17 
 
 Distribution and hosts ... 17 
 
 Life history 18 
 
 Parasites 20 
 
 Disease of the looper .... 22 
 
 Control 22 
 
 Amorbia 25 
 
 Distribution and hosts ... 25 
 
 Nature of injury 26 
 
 Life history 26 
 
 PAGE 
 
 Parasites 30 
 
 Control 30 
 
 June beetles 30 
 
 Life history 30 
 
 Control 31 
 
 Fuller's rose weevil 31 
 
 Brown mite 32 
 
 Distribution and hosts ... 32 
 
 Nature of injury 32 
 
 Life history 33 
 
 Dispersal 33 
 
 Predators 34 
 
 Control 34 
 
 Greenhouse thrips 34 
 
 Description 34 
 
 Nature of injury 34 
 
 Control 35 
 
 Broad-nosed grain weevil ... 35 
 
 Distribution and hosts ... 36 
 
 Description and habits ... 36 
 
 False chinch bug 37 
 
 Avocado pests of lesser importance 
 in California 37 
 
 Avocado pests of the world ... 38 
 
 Bibliography 44 
 
BIOLOGY AND CONTROL OF AVOCADO 
 INSECTS AND MITES 2 
 
 HOWARD L. McKENZIE 3 
 
 INTRODUCTION 
 The greatly increased planting of the avocado in recent years has 
 been accompanied by a corresponding increase in the amount of injury 
 caused by insect pests. Some of the insects attacking the avocado are 
 native to California and others are recorded as being of recent occur- 
 rence in the state. These pests include defoliating caterpillars and 
 beetles, a number of scale insects (of which the rather recently recorded 
 latania scale is the most important), the avocado brown mite, and a 
 native species of thrips. 
 
 The insect pests attacking the avocado in Florida and foreign coun- 
 tries have also been included in this bulletin. In a new industry, such as 
 the California avocado industry, it is important to know what pests 
 occur on the same crop in other sections or countries in order that proper 
 precautions may be taken to guard against the entrance of such insects; 
 a complete list of these is given in a later section. Two important pests 
 of the avocado in California, apparently, have already been introduced 
 from other localities. 
 
 The author wishes to express his appreciation to Professor H. J. 
 Quayle, of the Citrus Experiment Station, who directed the work re- 
 ported in this paper, and who read and corrected the manuscript. 
 Thanks are also due to Professor Harry S. Smith and to Mr. Walter 
 Ebeling for suggestions and corrections; to Professor P. H. Timberlake 
 for his identifications; and to Mr. D. P. Palmer, who at different times 
 rendered assistance. 
 
 i Received for publication, March 28, 1935. 
 
 2 Paper No. 318, University of California Citrus Experiment Station and Grad- 
 uate School of Tropical Agriculture, Eiverside, California. 
 
 3 Laboratory Assistant in Entomology. 
 
 [3] 
 
4 University of California — Experiment Station 
 
 KEY TO DIASPINE SCALES ATTACKING 
 THE AVOCADO IN CALIFORNIA 
 
 On account of the similarity of the diaspine scales of the avocado, espe- 
 cially those belonging to the genus Aspidiotus, it was deemed advisable 
 to construct a key. The key, together with the illustrations of the pygi- 
 dium 4 of each scale, should make possible an accurate determination. 5 
 This key has been prepared for inspectors and technical workers who 
 are competent to make such determinations. 
 
 A. Median pair of lobes on pygidium never more than twice as large as the second 
 
 or third pair of lobes on pygidium B 
 
 Median pair of lobes on pygidium extremely large, always three or four times 
 as large as the second or third pair of lobes on pygidium C 
 
 B. Circumgenital pores not present Aonidiella aurantii (Mask.) (fig. IB) 
 
 Circumgenital pores present D 
 
 C. Circumgenital pores present Aspidiotus lataniae Sign. (fig. 1C) 
 
 Circumgenital pores not present Aspidiotus camelliae Sign. (fig. IE) 
 
 D. Circumgenital pores numerous, always more than seven on each side of 
 
 pygidium Aspidiotus hederae (Vallot) (fig. ID) 
 
 Circumgenital pores few in number, never more than seven on each side of 
 
 pygidium Chrysomphalus dictyospermi (Morg.) (fig. 1A) 
 
 4 The pygidium is the posterior end of a diaspid scale. It is a fusion of the last five 
 or six of the ten abdominal segments normally characteristic of an insect. 
 
 5 The insect removed from beneath the wax covering need only be placed on a 
 slide in water, alcohol, or xylol (the latter preferred) and covered with a cover slide. 
 Such a temporary mount is sufficient to permit the determination of the species. 
 
Bul. 592J 
 
 Avocado Insects and Mites 
 
 Fig. 1. — A, Pygidium of dictyospermum scale, Chrysomphalus dictyospermi 
 (Morg.) ; B, pygidium of red scale, Aonidiella aurantii (Mask.) ; C, pygidium of la- 
 tania scale, Aspidiotus lataniae Sign., showing circumgenital pores (a), median lobes 
 (&), and outer pairs of lobes on pygidium (c) ; D, pygidium of ivy or oleander scale, 
 Aspidiotus hederae (Vallot) ; E, pygidium of the greedy scale, Aspidiotus camelliae 
 Sign. (Drawings A, B, D, and E after Dietz and Morrison.) 
 
University of California — Experiment Station 
 
 LATANIA SCALE 
 
 Latania scale, Aspidiotus lataniae Sign., is probably the most important 
 insect pest of the avocado in California. It has increased rapidly in the 
 last few years and has caused damage in many groves. The scale is 
 usually most abundant on the branches and twigs, but as the infesta- 
 tion increases, may also be found on the leaves and fruit. The smaller 
 
 
 
 
 
 
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 Fig. 2. — The latania scale, Aspidiotus lataniae Sign., on avocado 
 fruit, twigs, and leaves. (Courtesy of A. F. Kirkpatrick.) 
 
Bul. 592] 
 
 Avocado Insects and Mites 
 
 branches may be killed by a heavy infestation. The marketing quality of 
 the fruit is impaired because of the presence of the scale on the rind 
 (fig. 2) . As the fruits mature the insects cause protuberances to extend 
 from the rind down into the flesh, and when the rind is removed, corre- 
 sponding depressions are left in the flesh (fig. 3) . 
 
 History and Synonomy. — The latania scale, Aspidiotus lataniae Sign., 
 was described by Signoret (1869) 6 from a palm, Latania oarbonica, in a 
 
 i ■ *-**■ x 
 
 ** v ||Ev 
 
 
 ■ 
 
 Fig. 3. — Effects of latania scale on the fruit of avocado. Note the 
 depressions caused by the insects. (Courtesy D. B. Mackie, Cali- 
 fornia State Department of Agriculture.) 
 
 French conservatory. Apparently the scale was of foreign origin and its 
 mode of entry into the conservatory is not known. 
 
 Aspidiotus lataniae Sign, seems to have been defined by well-distin- 
 guished characters, since it has stood these sixty or more years. The main 
 confusion has been with A. cydoniae, a species since declared a synonym. 
 
 Distribution and Hosts. — Mackie (1931) reported the latania scale as 
 being rather generally present in California on avocados in San Diego, 
 Orange, and Los Angeles counties, with only a few light infestations 
 
 6 See "Bibliography," p. 44, for complete data on citations, which are referred to 
 in the text by author and date of publication. 
 
8 
 
 University of California — Experiment Station 
 
 found in Ventura County. He also gave statistics regarding the preva- 
 lence of the scale in each county during 1929 and 1930. Mackie also in- 
 cluded a list of the host plants of the world on which the insect has been 
 taken. This list includes some 163 host species and will be omitted from 
 this bulletin. With regard to host plants, latania scale in southern Cali- 
 fornia has not as yet become widespread. Aside from the avocado, which 
 appears to be its primary host, this scale has been found only on canna 
 
 Fig. 4. — The larva or crawler of latania 
 scale. (Greatly enlarged.) 
 
 lilies, gladiolus corms, Grevillea thelemanniana, raspberries, roses, and 
 Tamarix sp. However, an extensive survey of host plants has not been 
 made. 
 
 The insect is known to occur in Algeria, Australia, Belgium, Central 
 America, Channel Islands, China, Egypt, Galapagos Islands, Guam, 
 Guatemala, Germany, Hawaii, India, Mauritius, Mexico, Philippine 
 Islands, Rhodesia, South Africa, South America, Syria, Tahiti, and the 
 United States. 
 
 Life History. — The yellow eggs of latania scale hatch within a few 
 hours after they have been laid. The first-stage larva, or crawler (fig. 4) , 
 of the latania scale is sulfur yellow and measures about 0.1 inch in 
 length. There are four distinct segments to the antennae. The last seg- 
 ment possesses six spines, four of which arise from the sides and two at 
 
Bul. 592] Avocado Insects and Mites 9 
 
 the extreme tip. Each tarsus has a single claw, and attached to the tibia 
 are three knobbed hairs that extend beyond the tip of the claw. 
 
 The larvae do not, as a general rule, migrate far from the parent in- 
 sect. They usually settle within 8 hours and start to secrete wax, which 
 eventually becomes the scale covering. The only noticeable external 
 change that takes place after settling is the gradual expansion of the 
 insect and its wax covering. 
 
 Fig. 5. — The common chalcid, Aphytis diaspidis (Howard), the only 
 hymenopterons parasite that has been recovered from latania scale in 
 California. (Drawing by H. Compere.) 
 
 In 14 to 16 days after hatching, the insect molts. The difference in 
 appearance after the first molt is a clear-cut outer rim or margin of the 
 wax covering. The molting process requires from 2 to 3 days. The char- 
 ters of the pygidium of the second-stage female are quite distinct and 
 are apparently the same as those of the adult female except that they are 
 considerably smaller. 
 
 The second molt takes place in from 16 to 19 days after the first molt. 
 Upon completion of this molt the insect enters the adult stage. The 
 pygidium is characterized by one pair of conspicuous, well-developed 
 median lobes, notched externally; thus the distal half is slightly nar- 
 rower than the basal half. Circumgenital pores are also evident. A draw- 
 ing of the pygidium of the latania scale (see fig. 1C) will aid in deter- 
 mining this insect. In the adult female the ventral skins of the previous 
 stages may be found closely pressed on the surface of the leaf, twig, or 
 fruit beneath the insect. Crawlers appear within 26 to 30 days after the 
 
10 University of California — Experiment Station 
 
 second molt. The total length of the life cycle of this insect from egg to 
 adult is approximately two months (56 to 65 days) in summer at Enci- 
 nitas, California. 
 
 Female scales, isolated from birth beneath gelatin capsules, produced 
 young after two months. On the basis of this experiment, and because no 
 male specimens have been found, it is believed that the insect normally 
 reproduces parthenogenetically; that is, reproduction takes place with- 
 out fertilization. 
 
 Birds, insects, and man are responsible to some extent for the disper- 
 sion of this insect. Wind may also carry the individual crawler, or a leaf 
 bearing a colony of them, some distance. 
 
 Parasites and Predators. — The common chalcid, Aphytis diaspidis 
 (Howard) is the only hymenopterous parasite that is known to attack 
 the latania scale in California (fig. 5). It is small, less than 0.1 inch in 
 length, and yellowish. The eggs are a pale yellowish white, with a short 
 stalk at one end. The larvae are white, pear-shaped, and taper toward 
 the posterior end. The larvae feed on the body of the host. 
 
 The two-stabbed ladybird beetle, Chilocorus bivulnerus Muls., feeds 
 on latania scale. It measures from % to y 5 inch in length, is nearly 
 hemispherical, shining black, and has two red spots on the elytra. The 
 eggs are orange. The larvae are black and are covered with long 
 branched spines. When full-grown they measure about *4 inch in length. 
 They are also predacious upon the scale insects. 
 
 Blaisdell's ladybird, Lindorus lophanthae (Blaisdell) is approxi- 
 mately Y 12 inch long. The elytra are shining black, and the reddish 
 brown pronotum is frequently marked with a black blotch. 
 
 The blood-red ladybird, Cycloneda rubripennis Csy., is approxi- 
 mately V4 inch long. The elytra are bright scarlet with a short, trans- 
 verse basal, paler spot at each side of the scutellum, which is usually 
 black. 
 
 Control. — In June, 1931, several tolerance tests with fumigation were 
 made on seedling avocados on the Citrus Experiment Station grounds. 
 Some of the tender growth was burned with the higher dosages, but the 
 injury was not serious. Further tests were made later in the same plant- 
 ing to determine what effect seasonal changes would have on fumiga- 
 tion results. There were no scales on the trees on the Experiment Sta- 
 tion property, so counts could not be made. However, in September of 
 the same year, tests were made at Encinitas, California, which indicated 
 that fumigation gave a satisfactory kill of latania scale at all dosages 
 used (18 to 24 cc; see page 13 for explanation of dosage). With the ex- 
 ception of the highest dosage (24 cc) no tree damage occurred. 
 
Bul. 592] 
 
 Avocado Insects and Mites 
 
 11 
 
 Fumigation tests, with both liquid cyanide and powdered calcium 
 cyanide, were conducted during August and September, 1931, by D. F. 
 Palmer, Agricultural Inspector at Carlsbad, and A. F. Kirkpatrick. 
 
 Tests made in 1932-33 with several different oil sprays gave little 
 
 Fig. 6. — A 60 foot light-weight fumigation tent made from 350 
 sheeting. It will be noted that the avocado tree requires at least a 
 50-foot tent to cover it. One may hoist a tent over a much larger tree 
 by means of the 30-foot pole shown at the left. 
 
 promise of effectively controlling the latania scale on avocado, and at 
 the same time a considerable amount of tree defoliation occurred, as 
 well as a possible inhibition of the set of fruit. A highly refined medium 
 oil (grade 4) applied at 2 per cent strength is as heavy as may be used 
 with reasonable safety and at the same time secure a fair degree of kill 
 on the scale. 
 
12 
 
 University of California — Experiment Station 
 
 As compared with citrus-tree fumigation, which is a very old pro- 
 cedure, a number of new factors are involved in the fumigation of avo- 
 cado trees. One of these factors is the size of the avocado plantings, 
 many being but from one to five acres in extent. Still another factor is 
 
 Fig. 7. — Hoisting a fumigation tent over an avocado tree by means 
 of specially constructed 30-foot poles with pulleys and guy ropes 
 attached at the top end. 
 
 the greater danger of breaking the avocado branches as the tents are 
 pulled over them. This danger is obviated in part by the use of a light- 
 weight tent, made from 350 sheeting (fig. 6). 7 For the grower who has 
 only a few acres of avocados, one or more tents may be purchased, and 
 with the cooperation of a neighbor the tents may be hoisted over the 
 
 7 The term "350 sheeting" means that 3% yards of material 36 inches wide weighs 
 1 pound, or 4.57 ounces per square yard. 
 
Bul. 592] Avocado Insects and Mites 13 
 
 avocado trees by means of bamboo poles or with specially constructed 
 derricks (fig. 7). By this method, a few trees may be fumigated each 
 night. For such small plantings powdered calcium cyanide may be used, 
 with no particular hazard in connection with the handling of it and 
 with no special apparatus necessary for its use. 
 
 The fumigation dosage for a particular tree is measured by means of 
 cups of different sizes, ranging from 1 ounce to 5 or 6 ounces. The 
 amount of calcium cyanide, computed by the measurement of each tree, 
 may be determined by the use of a fumigation chart (table 1) . For avo- 
 cado trees, the dosage used is 2 ounces of calcium cyanide for each of the 
 units called for in the regular citrus-tree schedule (table 1, figures on 
 right side of columns). For example, a tree measuring 44 feet around 
 (figures at top of columns) and 34 feet over (figures at left side of 
 columns) calls for a dosage of 14 units (figures at right side of col- 
 umns). For dust cyanide, 14 units doubled (28 ounces) will give the 
 number of ounces for the size of tree indicated. When the liquid IICN is 
 used, the applicator should be set for 18 cc; hence the dosage will be 
 18 cc X 14, or 252 cc of liquid HCN. The exposure is 45 minutes. When 
 powdered cyanide is used, it is placed in a tin can (a 5-pound Cyanogas 
 can is often used) with a perforated bottom and with a long handle 
 attached for shaking the material on the ground under the tree. 
 
 Figures for calculating the distance over the tree are marked on the 
 fumigation tent, zero being at the top. When the tent has been thrown 
 over the tree, the figures nearest the ground, on each side of the tree, 
 should be added together. The distance around the tree may be measured 
 by a tape. 
 
 Fumigation should not be carried on when the wind is blowing suffi- 
 ciently to move the tents, or when the foliage or ground is wet, or in the 
 warm, bright sunlight. Fumigation is most effective during the months 
 of July, August, September, and October. 
 
 For larger plantings fumigation with liquid HCN is recommended 
 because of the larger number of tents required and the consequent 
 greater overhead cost against a single planting. In such work, where 
 thirty or more tents are employed, the use of liquid HCN is preferable 
 to the powdered calcium cyanide, because of the more rapid charging of 
 the tree by the liquid and the lower cost of the material. Experiments in 
 1934 with liquid HCN under the light-weight tents used in avocado 
 fumigation have proved effective in controlling the latania scale pro- 
 viding the 18 cc schedule is used. 
 
 Further details regarding the liquid HCN method of fumigation are 
 not given here because the use of that method is largely restricted to con- 
 
TABLE 1 
 
 Units of Liquid Hydrocyanic Acid (HON) Required to Fumigate Avocado Trees 
 of Different Sizes When 350 Sheeting is Used for Tenting Material* 
 
 12t 
 
 14 
 
 16 
 
 18 
 
 20 
 
 22 
 
 24 
 
 26 
 
 28 
 
 30 
 
 32 
 
 34 
 
 10-2 
 
 10-2 
 
 10-3 
 
 10-3 
 
 10-3 
 
 12-4 
 
 12-4 
 
 14-5 
 
 16-5 
 
 16-5 
 
 18-6 
 
 18-6 
 
 12-3 
 
 12-3 
 
 12-3 
 
 12-4 
 
 12-4 
 
 14-4 
 
 14-5 
 
 16-5 
 
 18-6 
 
 18-6 
 
 20-6 
 
 20-7 
 
 14-3 
 
 14-3 
 
 14-4 
 
 14-4 
 
 14-4 
 
 16-5 
 
 16-5 
 
 18-5 
 
 20-6 
 
 20-6 
 
 22-7 
 
 22-7 
 
 16-4 
 
 16-4 
 
 16-4 
 
 16-4 
 
 16-5 
 
 18-5 
 
 18-5 
 
 20-6 
 
 22-6 
 
 22-7 
 
 24-7 
 
 24-7 
 
 18-4 
 
 18-4 
 
 18-4 
 
 18-5 
 
 18-5 
 
 20-5 
 
 20-6 
 
 22-6 
 
 24-7 
 
 24-7 
 
 26-7 
 
 26-8 
 
 
 
 
 
 20-5 
 
 22-6 
 
 22-6 
 
 24-6 
 
 26-7 
 
 26-7 
 
 28-8 
 
 28-8 
 
 
 
 
 
 22-5 
 
 2i-6 
 
 24-6 
 
 26-7 
 
 28-7 
 
 28-7 
 
 30-8 
 
 30-9 
 
 
 
 
 
 24-6 
 
 
 
 
 
 30-8 
 
 32-9 
 
 32-10 
 34-/0 
 36-// 
 
 36 
 
 38 
 
 40 
 
 42 
 
 44 
 
 46 
 
 48 
 
 50 
 
 52 
 
 54 
 
 56 
 
 18-6 
 
 20-7 
 
 20-7 
 
 20-7 
 
 22-8 
 
 22-8 
 
 26-/0 
 
 26-// 
 
 30-/ 3 
 
 30-/4 
 
 30-/4 
 
 20-7 
 
 22-7 
 
 22-7 
 
 22-7 
 
 24-9 
 
 24-9 
 
 28-// 
 
 28-/2 
 
 32-/5 
 
 32-/5 
 
 32-/5 
 
 22-7 
 
 24-8 
 
 24-8 
 
 24-8 
 
 26-/0 
 
 26-/0 
 
 30-/2 
 
 30-/3 
 
 34-/6 
 
 34-/7 
 
 34-/7 
 
 24-8 
 
 26-9 
 
 26-9 
 
 26-9 
 
 28-// 
 
 28-// 
 
 32-/4 
 
 32-/4 
 
 36-/7 
 
 36-/8 
 
 36-/8 
 
 26-8 
 
 28-9 
 
 28-/0 
 
 28-/0 
 
 30-/2 
 
 30-/2 
 
 34-/5 
 
 34-/5 
 
 38-/8 
 
 38-/9 
 
 38-20 
 
 28-9 
 
 30-/0 
 
 30-// 
 
 30-// 
 
 32-/ 3 
 
 32-/S 
 
 36-/6 
 
 36-/7 
 
 40-20 
 
 40-2/ 
 
 40-2/ 
 
 30-/0 
 
 32-// 
 
 32-/2 
 
 32-/2 
 
 34-/4 
 
 34-/4 
 
 38-/7 
 
 38-/8 
 
 42-2/ 
 
 42-22 
 
 42-23 
 
 32-/0 
 
 34-/2 
 
 34-/3 
 
 34-/3 
 
 36-/5 
 
 36-/5 
 
 40-/8 
 
 40-/9 
 
 44-23 
 
 44-23 
 
 44-24 
 
 34-// 
 
 36-/3 
 
 36-/4 
 
 36-/4 
 
 38-/6 
 
 38-/7 
 
 42-20 
 
 42-2/ 
 
 46-24 
 
 46-25 
 
 46-26 
 
 36-/2 
 
 38-/4 
 
 38-/4 
 
 38-/5 
 
 40-/7 
 
 40-/8 
 
 44-2/ 
 
 44-22 
 
 48-25 
 
 48-26 
 
 48-27 
 
 38-/S 
 
 
 
 40-/6 
 
 42-. 8 
 
 42-/9 
 44-20 
 
 
 46-23 
 48-24 
 50-25 
 
 50-26 
 
 50-27 
 
 50-28 
 52-30 
 
 58 
 
 60 
 
 62 
 
 64 
 
 66 
 
 68 
 
 70 
 
 72 
 
 74 
 
 76 
 
 78 
 
 30-/4 
 
 32-/6 
 
 34-/8 
 
 34-/8 
 
 36-2/ 
 
 40-25 
 
 40-25 
 
 42-28 
 
 44-30 
 
 46-33 
 
 48-36 
 
 32-/6 
 
 34-/8 
 
 36-20 
 
 36-20 
 
 38-22 
 
 42-26 
 
 42-27 
 
 44-30 
 
 46-32 
 
 48-35 
 
 50-38 
 
 34-/7 
 
 36-/9 
 
 38-2/ 
 
 38-22 
 
 40-24 
 
 44-28 
 
 44-29 
 
 46-32 
 
 48-34 
 
 50-37 
 
 52-40 
 
 36-/9 
 
 38-2/ 
 
 40-23 
 
 40-24 
 
 42-26 
 
 46-30 
 
 46-3/ 
 
 48-34 
 
 50-36 
 
 52-39 
 
 54-42 
 
 38-20 
 
 40-22 
 
 42-25 
 
 42-25 
 
 44-28 
 
 48-32 
 
 48-33 
 
 50-36 
 
 52-38 
 
 54-4/ 
 
 56-44 
 
 40-22 
 
 42-24 
 
 44-27 
 
 44-27 
 
 46-29 
 
 50-34 
 
 50-35 
 
 52-38 
 
 54-40 
 
 56-43 
 
 58-47 
 
 42-23 
 
 44-26 
 
 46-28 
 
 46-29 
 
 48-3/ 
 
 52-36 
 
 52-37 
 
 54-40 
 
 56-42 
 
 58-45 
 
 
 44-25 
 
 46-27 
 
 48-30 
 
 48-3/ 
 
 50-33 
 
 54-38 
 
 54-39 
 
 56-42 
 
 48-44 
 
 
 
 46-27 
 
 48-29 
 
 50-3/ 
 
 50-32 
 
 52-35 
 
 56-40 
 
 56-4/ 
 
 58-43 
 
 
 
 
 48-28 
 
 50-30 
 
 52-33 
 
 52-34 
 
 54-37 
 
 58-4/ 
 
 58-42 
 
 
 
 
 
 50-30 
 
 52-32 
 
 54-35 
 
 54-36 
 
 56-39 
 
 
 
 
 
 
 
 52-3/ 
 
 54-33 
 
 56-36 
 
 56-38 
 
 58-40 
 
 
 
 
 
 
 
 54-32 
 
 56-35 
 
 58-38 
 
 58-39 
 
 
 
 
 
 
 
 
 
 58-36 
 
 
 
 
 
 = 
 
 
 
 
 
 80 
 
 82 
 
 84 
 
 86 
 
 88 
 
 
 
 
 
 
 50-38 
 
 52-4/ 
 
 54-44 
 
 56-50 
 
 58-54 
 
 
 52-40 
 
 54-43 
 
 56-47 
 
 58-53 
 
 60-56 
 
 
 
 
 
 
 
 54-42 
 
 56-45 
 
 58-50 
 
 60-55 
 
 62-58 
 
 
 
 
 
 
 
 56-44 
 
 58-48 
 
 60-55 
 
 62-57 
 
 64-60 
 
 
 
 
 
 
 
 58-47 
 
 60-53 
 
 62-57 
 
 64-60 
 
 66-65 
 
 
 
 
 
 
 
 60-50 
 
 62-55 
 
 64-59 
 
 66-64 
 
 68-70 
 
 
 
 
 
 
 
 62-53 
 
 64-57 
 
 66-60 
 
 68-66 
 
 
 
 
 
 
 
 
 64-55 
 
 66-59 
 
 68-64 
 
 
 
 
 
 
 
 
 
 66-57 
 
 68-60 
 
 
 
 
 
 
 
 
 
 
 68-59 
 
 
 
 
 
 
 
 
 
 
 
 * Adapted from: Quayle, H. J. Biology and control of citrus insects and mites. California Agr. Exp. 
 Sta. Bui. 542:74 (table 1). 1932. 
 
 t Figures across top of columns represent distance around in feet, those on left side of columns distance 
 over in feet. Italic figures on right side of columns represent dosage in units of HCN. When calcium cyan- 
 ide is used, the figures on the right side of columns, when doubled, give the number of ounces required. 
 
Bul. 592] Avocado Insects and Mites 15 
 
 tractors and others especially equipped for fumigation work on a large 
 scale. 8 
 
 Perhaps the parts of the avocado tree most susceptible to fumigation 
 injury are the blossoms and young fruit. The tender growth may burn 
 but new growth rapidly appears and the tree soon recovers. In the case 
 of blossoms and young fruit, however, such is not the case. Much re- 
 mains to be learned about the fumigation of avocado trees, and this sub- 
 ject is still under investigation by the Citrus Experiment Station. 
 
 DICTYOSPERMUM SCALE 
 
 The dictyospermum scale, Chrysomphalus dictyospermi (Morgan), has 
 been found in California in the avocado-growing areas at Whittier. To 
 date it has caused little damage in this region, but eventually it may 
 become an important pest of avocados in the state. In Florida the dictyo- 
 spermum is the most destructive scale-insect pest of avocados. A draw- 
 ing of the pygidium of this scale (fig. 1A) will aid in its identification. 
 
 The dictyospermum scale attacks primarily the twigs and branches, 
 and as the infestation becomes greater the foliage is attacked. Branches 
 and twigs that have been severely attacked by this scale become rough- 
 ened, crack, and fail to function properly. 
 
 For control see latania scale. 
 
 GREEDY SCALE 
 
 The greedy scale, Aspidiottis camelliae Sign., is frequently found on 
 avocados. It is so similar to the latania scale that growers are usually 
 confused as to its identity. The pygidium of this scale (fig. IE) may be 
 compared with that of the latania scale. 
 For control see latania scale. 
 
 IVY OR OLEANDER SCALE 
 
 The ivy or oleander scale, Aspidiotus hederae (Vallot), like the above 
 species, is difficult to separate from the latania scale. The pygidium 
 (fig. ID) is the only certain means of distinguishing this scale from the 
 latania and greedy scales. 
 For control see latania scale. 
 
 RED SCALE 
 
 The red scale, Aonidiella aurantii (Mask.), occasionally attacks the avo- 
 cado, especially where the avocado grove is near a citrus planting. 
 
 s Growers wishing further details in regard to the liquid HCN method of fumiga- 
 tion are referred to : Quayle, H. J. Biology and control of citrus insects and mites. 
 California Agr. Exp. Sta. Bul. 542:72-79. 
 
16 University of California — Experiment Station 
 
 Wherever this scale occurs, it usually increases rather rapidly and con- 
 trol measures are necessary. For identification see pygidium of red 
 scale (fig. LB). 
 
 For control see latania scale. 
 
 SOFT BROWN SCALE 
 
 The soft brown scale, Coccus hesperidum (Linn.), (fig. 8) is common in 
 California on avocados, especially along the coast near Encinitas and 
 Carlsbad. This scale produces a considerable amount of honeydew and 
 is responsible for much smutting of the foliage. There are several gen- 
 erations a year. 
 
 Fig. 8. — Soft brown scale, Coccus hesperidum (Linn.), on a twig of avocado. 
 
 There are many parasites which control the soft brown scale. Fre- 
 quently, however, ants are present in large numbers, feeding on the 
 honeydew excreted by the scales. In such cases it is necessary to control 
 the ants in order that the parasites may work undisturbed. 9 
 
 BLACK SCALE 
 
 The black scale, Saissetia oleae (Bernard), is occasionally found on avo- 
 cados in California but, with an occasional exception, it is of no particu- 
 lar importance. 
 
 Treatment should be made when the insects are all in the younger 
 stages, at which time they are more readily killed. Satisfactory results 
 may be obtained by fumigation or a light-oil spray. 
 
 OMNIVOROUS LOOPER 
 
 The omnivorous looper, Sabulodes caber at a Gn., is one of the most im- 
 portant leaf-feeding insects of the avocado. Sometimes these insects 
 become numerous enough to strip the tree of practically its entire 
 foliage. 
 
 9 Readers desiring further information in regard to Argentine ant control may 
 consult: Quayle, H. J. Biology and control of citrus insects and mites. California 
 Agr. Exp. Sta. Bui. 542:64. 1932. 
 
Bul. 592 
 
 Avocado Insects and Mites 
 
 17 
 
 History and Synonomy. — The omnivorous looper belongs to the order 
 Lepidoptera, family Geometridae (measuring worms). According to 
 the literature to date this insect is native to California. It was originally 
 described by Guenee (1857), who also gave the following synonyms: 
 Sabulodes aegrotata Guenee and 8. forficaria Guenee. Walker (1860) 
 described this moth as Sabulodes arsenaria. 
 
 Fig. 9. — Hatched eggs of the omnivorous looper, Sabulodes caberata (Gn.), on 
 a leaf of the avocado. 
 
 Distribution and Hosts. — The omnivorous looper is distributed gen- 
 erally throughout California but has not been recorded in any of the 
 other western states. 
 
 This insect has a large number of host plants, of which the following, 
 listed by Essig (1926), are representative: acacia, alder, aralia, avo- 
 cado, box elder, buckeye, California laurel, California Christmas berry, 
 cherry, chestnut, clematis, daisy, elm, English ivy, eucalyptus, geran- 
 ium, ginkgo, grevillea, groundsel, honeysuckle, lemon, lemon verbena, 
 magnolia, maple, olive, orange, passion vine, pecan, pepper tree, rose, 
 sumac, sycamore, tecoma, violet, black walnut, and willow. The present 
 writer has also taken specimens feeding on a species of privet in San 
 Diego County. 
 
18 
 
 University of California — Experiment Station 
 
 Life History.— The eggs of Sabulodes caberata Gn. are ovoid in shape, 
 about Me i ncn long, and are a little larger at the anterior end (fig. 9). 
 There are several small, round tubercles arranged in a circle around the 
 anterior or large end of the egg. The eggs are deposited in clusters on 
 
 Fig. 10. — The omnivorous looper: A, first-stage larva; B, second-stage larva; 
 C, third-stage larva; D, fourth-stage larva; E, fifth-stage larva. 
 
 the undersides of leaves. Each cluster may consist of from 3 to 80 eggs. 
 One side of each egg is laid flat on the leaf. Just after the eggs have been 
 laid they are metallic green, but in two days turn to a chocolate brown. 
 They hatch within 8 or 9 clays, according to temperature and humidity. 
 When the larva emerges from the egg, it is pale yellow and measures 
 
Bul. 592] 
 
 Avocado Insects and Mites 
 
 19 
 
 about y 1Q inch in length (fig. 10 A). It is very active and immediately 
 begins feeding on the young, tender growth. Only the epidermis is eaten 
 from the leaf, for until it approaches the first molt the larva is unable 
 to make holes in the leaf. If disturbed while on the tree, the insect drops 
 suddenly, spinning a silken thread from which it may hang suspended 
 in the air for some time. These silken threads may attain lengths of from 
 1 to 3 feet. 
 
 Fig. 11.— Damage caused by the omnivorous looper. 
 
 The second-stage larva (fig. 105) is % i ncn i n length and is charac- 
 terized by two dark bands along the sides of the body. 
 
 The third-stage larva (fig. IOC) is y 2 inch long and has four dark 
 bands along the sides of the body. These bands fuse toward the posterior 
 end of the body and extend down the hind pair of prolegs. 
 
 The fourth-stage larva (fig. 102)) measures a little more than % inch 
 in length and is practically identical with the larva of the previous 
 stage except that it has two black dots on the front of the head. 
 
 The fifth-stage larva (fig. 10E) measures from 2 to 2% inches long 
 and about 14 inch wide. 
 
20 
 
 University of California — Experiment Station 
 
 The larvae of the omnivorous looper vary from yellow to pale green 
 or pink, with yellow, brown, or green stripes on the sides and back and 
 with black markings over the body. During the third, fourth, and fifth 
 larval stages, the insect feeds voraciously (fig. 11). One large avocado 
 leaf may easily be consumed in 24 hours by a larva of the fifth stage. The 
 duration of the larval stages of the late summer brood is shown in 
 
 table 2. 
 
 TABLE 2 
 
 Duration of Larval Stages of the Omnivorous Looper* 
 
 Stage 
 
 Minimum, 
 days 
 
 Maximum, 
 days 
 
 Average, 
 days 
 
 First 
 
 5 
 3 
 4 
 4 
 
 9 
 
 25 
 
 11 
 10 
 12 
 13 
 19 
 
 65 
 
 7 67 
 
 
 5 76 
 
 Third 
 
 Fourth 
 
 Fifth 
 
 7 35 
 7 65 
 14 80 
 
 Total 
 
 43 23 
 
 * Late summer brood under outdoor conditions existing at Encinitas, California. 
 
 The third and fourth-stage larvae become sluggish and commonly 
 spin a web in a leaf fold, or between two or more leaves, in which to rest 
 during the day. As the fifth-stage larva approaches pupation, it shrinks 
 somewhat and turns white (fig. 12, left). 
 
 The pupa (fig. 12) is approximately V/± inches long. It is pearly 
 white but becomes a dark brown as the wings develop. It is usually 
 found webbed between two leaves or inside one leaf which has been 
 pulled together for the purpose. The pupal period lasts from 13 to 33 
 days, according to climatic conditions. 
 
 The adult moth, Sabulodes caberata Gn., (fig. 13) is dull brown or 
 yellow and has a wing expanse of from 1% to 2 inches. Some of the fe- 
 male moths that were caught in the field laid from 200 to 300 eggs. The 
 moths are nocturnal but may be found during the day clinging to the 
 undersides of leaves with their wings spread. If disturbed, however, 
 they fly rapidly in a broken up-and-down movement for several yards; 
 but when they alight they remain motionless. The moths die within two 
 to three weeks after emerging from the cocoons. The total length of the 
 life cycle of this insect from egg to adult is approximately iy 2 months 
 in summer at Encinitas. There appear to be from five to six generations 
 a year. 
 
 Parasites. — The most important parasite of the omnivorous looper is 
 an insect belonging to the order Hymenoptera, family Braconidae, 
 namely, Habrobracon xanthonotus (Ashm.) (fig. 14). The female para- 
 
Bul. 592] Avocado Insects and Mites 21 
 
 site stings the caterpillar near the head and as a general rule attacks 
 from the front. This results in paralysis of the caterpillar. The parasite 
 will not, apparently, oviposit on a dead individual. Its eggs are ex- 
 tremely small and are almost invisible to the unaided eye. They are elon- 
 gate and pearly white. The eggs are laid on various parts of the cater- 
 pillar and hatch within 1 or 2 days. The larva is whitish, and the body is 
 
 Fig. 12. — Fifth-stage larvae of the omnivorous looper (left) ; the white indi- 
 vidual is approaching pupation. (Original.) Newly formed pupae shown at the 
 right. (Courtesy of C. J. Pierson.) 
 
 covered with small protrusions. As it approaches pupation it works its 
 way beneath the decaying caterpillar to pupate. The larval period ter- 
 minates in 4 to 6 days. The pupae are enclosed in flimsy white cocoons. 
 These cocoons are found in clusters, from 18 to 22 cocoons in each clus- 
 ter. The pupal period lasts from 8 to 10 days. The adults emerge through 
 round holes at the ends of the cocoons. 
 
 This parasite produced at least 70 per cent parasitism of the omnivor- 
 ous looper in 1932, yet this is not sufficient for control. 
 
 Trichogramma minutum Riley is another insect enemy of the omniv- 
 orous looper. It is a cosmopolitan parasite on the eggs of many insects. 
 A single specimen of the parasite Brachymeria ovata (Say) was recov- 
 ered from a discolored pupa of the omnivorous looper. One specimen of 
 Telenomits was reared from an egg of the omnivorous looper. It is jet 
 black and very small. This insect is a hymenopterous parasite belonging 
 to the family Scelionidae. Ophion abnormis var. magniceps Hooker, a 
 
22 
 
 University of California — Experiment Station 
 
 hymenopterous parasite belonging to the family Ichneumonidae, at- 
 tacks the pupae of the omnivorous looper in California and is common 
 in the San Francisco Bay region. It measures from y 2 to % inch in 
 length and is amber brown with many conspicuous white lines and 
 specks on the head and thorax. 
 
 Disease of the Looper. — The omnivorous looper is attacked by a fun- 
 gus disease similar to the wilt disease of the silkworm. It appears to be 
 an intestinal disease and seems to attack only caterpillars of the third, 
 
 — 
 
 " ■ ' ~\ 
 
 
 
 « * 
 
 
 i 1 x \ 
 
 
 
 
 
 ^Hi 
 
 x ■.* 
 
 t& 
 
 < % 
 
 
 . f 
 
 
 
 ; ■ # ■ 
 
 
 ■A 
 
 
 
 
 
 m 
 
 
 
 ;?/?' — '. .'' ■' 
 
 
 jt . 
 
 
 
 'w it, *P4k^ 
 
 
 iW ■•'• 
 
 
 
 j -■'■'' 
 
 
 • % ' 
 
 
 
 , ■;*'.' '.■/ : -/:■■? 
 
 
 ■i%. 
 
 \ 
 
 / 
 
 
 Fig. 13. — Adult female of the omnivorous looper with Avings spread. 
 
 fourth, and fifth stages (fig. 15). Out of 88 caterpillars used to carry 
 out a certain experiment, only 2 pupated; the remainder Avere attacked 
 by this organism. 
 
 During the latter part of 1932 and 1933, the looper was successfully 
 controlled by the fungus disease. Yet it is well to keep in mind the fact 
 that the principal damage to the trees had occurred before the cater- 
 pillars became infected by this disease. 
 
 Control. — After several preliminary experiments it was found that 
 the looper moths were attracted to ordinary electric light. Light traps 
 were built with a 50-watt bulb that was hung suspended from a cord a 
 few inches above a galvanized tub filled with water with a thin film of 
 kerosene on the surface. These traps were so designed that when the 
 moth swooped toward the light it would fall into the tub. Tests were 
 
Bul. 592] Avocado Insects and Mites 23 
 
 conducted to see what effect these light traps would have on the control 
 of this pest. Since the initial number of moths caught in the light traps 
 was relatively small as compared to the number still left in the field, 
 light-trap experiments were discontinued. 
 
 In bait-trap experiments a material called Diamalt was used. This 
 poison bait is made up of the following ingredients : 
 
 Diamalt 1 pint 
 
 Water 19 pints 
 
 Yeast (compressed) ._•. 1 cake 
 
 Fig. 14. — Habrobracon xanthonotus (Ashm.), a parasite 
 of the looper. Adult female with wings spread. 
 
 The Diamalt was first put into water and stirred until dissolved. The 
 yeast was then dissolved in a small amount of water and added to the 
 Diamalt solution. The mixture was poured into twenty-two pans, with 
 wire handles. Each pan was hung over one end of an irrigation stand- 
 ard, some 12 feet above the ground. In one week the pans were exam- 
 ined and only 50 moths were found. 
 
 Owing to the fact that the fungus disease cannot be depended upon 
 every year, and to the fact that the parasites and light and bait traps 
 are not effective in controlling the omnivorous looper, mechanical meth- 
 ods must be relied upon. Several tests were made with poison dusts. 
 J. D. Hoffman's avocado grove at Encinitas, California, was first arbi- 
 trarily divided into four one-acre plots. In each of these plots, four trees 
 
24 
 
 University of California — Experiment Station 
 
 of different varieties of avocado were chosen. Fumigation tents were 
 then spread under the four trees in each plot and the live caterpillars on 
 each tree counted. The four plots were dusted, one with standard lead 
 arsenate, one with basic lead arsenate, one with cryolite (synthetic), 
 and one with barium fluosilicate. Thirty pounds of each insecticide were 
 
 
 Fig. 15. — Last-stage larvae of the omnivorous 
 looper that have succumbed from the attack of 
 the wilt disease. 
 
 mixed with 70 pounds of diatoinaceous earth. The remainder of the 
 grove served as a check plot. The caterpillars killed by the poison dusts 
 dropped to the tents spread on the ground below the trees. These dead 
 caterpillars were counted, and the data indicated that comparable re- 
 sults were obtained through the use of basic and standard lead arsenate. 
 Later (1933-34) it was found that standard lead arsenate, applied as a 
 spray, proved more effective than the basic lead arsenate. The spray 
 recommended is as follows : 
 
 Standard lead arsenate 4 pounds 
 
 Blood albumin spreader 6 ounces 
 
 Water _ 100 gallons 
 
Bul. 592] 
 
 Avocado Insects and Mites 
 
 25 
 
 It is advisable to use 30 per cent of the basic lead arsenate plus 70 per 
 cent diatomaceous earth or sulfur if mites are present, applied when the 
 trees are in blossom and when the fruits are small. 
 
 By studying the life history of the insect it was possible to correlate 
 the time of application of the poison with the life stage of the insect that 
 was most susceptible to control measures. In this case the first applica- 
 tion was made while the greatest number of individuals were in the first 
 larval stage. The second application should be timed to reach the young 
 caterpillars of the following brood before they have a chance to mature. 
 However, when the standard lead arsenate is applied as a spray, the 
 lasting qualities are much greater. In the case of overhead irrigation, 
 the applications should be made soon after irrigating, because better 
 results are obtained if the insecticide is left on the tree as long as pos- 
 sible. 
 
 AMORBIA 
 
 Amorbia essigana Busck is a member of the order Lepidoptera, family 
 Tortricidae (leaf rollers). In 1922 the first record of its occurrence in 
 
 Fig. 16. — Tnjury to small avocado fruits by 
 amorbia, Amorbia essigana Busck. 
 
 California was made by E. 0. Essig, who, in a letter to Busck, reported 
 it as doing considerable damage to the foliage in avocado orchards. 
 According to Busck (1929) it is allied to the larger California species, 
 Amorbia cuneana Walsingham, and may eventually prove to represent 
 not more than a variety or possibly a subspecies of cuneana. 
 
 Distribution and Hosts. — According to Busck this species is found in 
 
26 
 
 University op California — Experiment Station 
 
 San Diego and Los Angeles counties, California. The writer has also 
 collected specimens in Orange County. The amorbia seems to prefer 
 only one host plant, the avocado. 
 
 Nature of Injury. — The injury caused by the amorbia is important 
 because it is more noticeable on the avocado fruits than on the leaves. 
 
 Fig. 17. — A fruit of the Anaheim variety showing ultimate 
 result of amorbia injury. 
 
 Young fruits are most frequently attacked and the scarring (fig. 16) 
 enlarges as the fruits mature (fig. 17) . This naturally reduces the qual- 
 ity of the fruit and impairs its market value. Injury to the leaves (fig. 
 18) may become of considerable importance and yet it is slight com- 
 pared to that of the omnivorous looper. Injury to the leaves consists 
 primarily in a skeletonizing effect. 
 
 Life History. — The eggs (fig. 19) of the amorbia are usually de- 
 
Bul. 592] 
 
 Avocado Insects and Mites 
 
 27 
 
 posited on the top side of the leaf along' the midrib. They are greenish 
 and laid in flat masses that may consist of from 5 to 98 eggs. A single 
 moth may lay from 400 to 500 eggs. The incubation period varies from 
 13 to 15 days. 
 
 Fig. 18. — Characteristic webbing and leaf injury of amorbia 
 on the avocado. 
 
 There are seven larval stages of this insect. Pupation may occur, 
 however, after the fifth or sixth stages as well as after the seventh. The 
 first-stage caterpillar is small and yellowish green. The larvae of the 
 second, third, fourth, fifth, and sixth stages are somewhat alike except 
 for size. The seventh-stage larva (fig. 20) measures from % inch to 1% 
 inches in length. Considerable damage is done to the fruits touching" one 
 another, because the larvae will web between the fruits and eat the 
 
28 
 
 University of California — Experiment Station 
 
 epidermis of the avocado. More larvae mature on the foliage, however, 
 than on the fruits. Even before the first molt the young larvae usually 
 web two leaves together, and in these chambers they remain hidden 
 
 ,<<*• 
 
 W^ 
 
 Fig. 19. — Greenish egg mass of amorbia. (Greatly 
 enlarged.) 
 
 during the daytime. If the leaves are pulled apart the larvae will wrig- 
 gle violently and fall to the ground. The length of the larval stages of 
 the late summer brood is given in table 3. 
 
 Section of 
 
 mid - dorsal view 
 
 Fig. 20. — Last-stage larva of amorbia. (Drawing by C. M. Dammers; greatly 
 
 enlarged.) 
 
Bul. 592] 
 
 Avocado Insects and Mites 
 
 29 
 
 The pupa (fig. 21) is from % to almost % inch in length. The newly 
 formed pupa is pale green, but as the wings develop it becomes more and 
 more pigmented until finally it turns chocolate brown. The pupae are 
 
 Fig. 21. — Cast pupal skin of amorbia on 
 avocado leaf. (Slightly enlarged.) 
 
 usually found between two leaves webbed together for that purpose. The 
 pupal stage lasts from 11 to 21 days, with an average of 17 days. 
 
 The adult moth of the amorbia has reddish-brown (chocolate) fore- 
 wings (fig. 22) . It has a wing expanse of about one inch. The moths are 
 seldom seen during the day unless disturbed from their resting places 
 on the undersides of leaves. The total length of the life cycle of this in- 
 sect from egg to adult is approximately two months in summer at Enci- 
 
 TABLE 3 
 Duration of Larval Stages of Amorbia* 
 
 Stage 
 
 Minimum, 
 days 
 
 Maximum, 
 days 
 
 Average, 
 days 
 
 First 
 
 7 
 3 
 3 
 3 
 4 
 4 
 7 
 
 31 
 
 21 
 11 
 14 
 11 
 19 
 16 
 20 
 
 112 
 
 13 32 
 
 Second 
 
 Third 
 
 Fourth 
 
 6 
 6 
 6 
 8 
 10 
 12 
 
 63 
 
 70 
 29 
 05 
 
 Fifth 
 
 05 
 
 Sixth 
 
 31 
 
 Seventh 
 
 Total 
 
 87 
 59 
 
 * Late summer brood under outdoor conditions existing at Encinitas, California. 
 
30 University of California — Experiment Station 
 
 nitas. There appear to be four or five generations a year, but further 
 study will be needed to verify this fact. 
 
 Parasites. — One parasite was found attacking the amorbia. It is an 
 egg parasite, Tricho gramma minutum Riley, also parasitic on the om- 
 nivorous looper. It is not effective in controlling the amorbia. 
 
 Control. — A light-trap experiment used with the omnivorous looper 
 was again conducted to see what effect ordinary electric light would 
 
 in Y m p 
 
 Fig. 22. — Adult female of the amorbia moth. (Drawing by C. M. Dammers.) 
 
 have on the amorbia. The preliminary data indicate that light traps are 
 not effective in controlling this moth. 
 
 Like the light traps, bait traps used for the omnivorous looper ap- 
 peared to be ineffective in controlling the amorbia. With the use of Dia- 
 malt bait, only 17 moths were captured in one week. 
 
 The control of this insect is the same as for the omnivorous looper. 
 However, since there appears to be a considerable overlapping of gen- 
 erations, several applications of standard lead arsenate spray are neces- 
 sary in order to keep the amorbia in check. Applications should be made 
 at one-month intervals. 
 
 JUNE BEETLES 
 
 Occasionally outbreaks of two species of June beetles (Coleoptera, Sca- 
 rabaeidae), Serica fimbriata Lee. (fig. 23) and S. alternata Lee, are 
 observed on young avocado trees. They are medium-sized, somewhat 
 cylindrical, robust, usually smooth or velvety brown, with faintly stri- 
 ated elytra. Serica fimbriata is the larger of the two beetles, measuring 
 approximately % inch in length. Serica alternata is % inch long and of 
 uniform shiny brown color. 
 
 Life History. — The larvae or grubs of these June beetles are usually 
 
Bul. 592] Avocado Insects and Mites 31 
 
 thick, wrinkled, white or yellow, somewhat hairy, enlarged posteriorly 
 and usually in the form of a crescent, with well-developed legs. 
 
 The adults are nocturnal and the larvae feed underground on decayed 
 and living vegetation. As a general rule, these beetles are most abundant 
 wherever there is native vegetation near a cultivated avocado grove. 
 
 Control. — A spray of standard lead arsenate, used at the rate of 4 
 pounds to 100 gallons of water plus 6 ounces of blood albumin spreader, 
 is only fairly satisfactory in controlling the Serica beetles. If the trees 
 are in bloom, application of a dust of 30 pounds of basic lead arsenate 
 plus 70 pounds of diatomaceous earth is recommended. 
 
 Fig. 23. — June beetle, Serica flmbriata Le 
 
 FULLER'S ROSE WEEVIL 
 
 Fuller's rose weevil Pantomorus godmani (Crotch), measures approxi- 
 mately % inch in length and is a uniform pale brown. The eggs of this 
 weevil are elliptical, pale yellow, and smooth; they measure about %5 
 inch in length. In the spring of the year, the eggs are laid in irregular 
 rows in masses, either on the ground near the host, under the bark of 
 trees, or near the bases of smaller plants. The legless white larvae or 
 grubs are about % inch long and live on the roots of plants. Pupation 
 takes place in a cell in the ground. 
 
 One very serious infestation of this weevil was observed in 1933 at 
 Encinitas on young avocado trees. 
 
 Since the adults cannot fly it is possible to prevent them from ascend- 
 ing the avocado trees by a tanglefoot band, 10 provided that the branches 
 of the tree do not touch the ground. Where bands are not used, see con- 
 trol for the omnivorous looper. 
 
 io Paraffin should be placed around the trunk of the avocado tree to prevent in- 
 jury to the bark caused by the tanglefoot. After the paraffin has hardened suffi- 
 ciently, the tanglefoot band may be placed around the trunk over the paraffin. 
 
32 
 
 University of California — Experiment Station 
 
 Cryolite apparently kills the fuller's rose weevil more effectively than 
 standard lead arsenate, but the injury it causes to the avocado tree 
 along the coast renders it unsafe to use. 
 
 BROWN MITE 
 
 The avocado brown mite, Paratetranychus y other si McG., is a pest of 
 the avocado and in many instances causes serious damage to the trees. 
 Since these mites are almost invisible to the unaided eye, and because 
 the foliage does not show injury until the mites become abundant, the 
 
 Fig. 24. — The avocado brown mite, Paratetranychus yothersi 
 McG: a, b, egg; c, larva; d, first nymph ; e, second nymph; /, adult 
 female. (Courtesy United States Department of Agriculture.) 
 
 actual injury done is usually underestimated. If climatic conditions are 
 not favorable for the mites the injury is not important and in such cases 
 treatment is unnecessary. If the mites become abundant, however, con- 
 trol measures should be resorted to immediately. 
 
 Distribution and Hosts. — The avocado brown mite belongs to the 
 order Acarina, family Tetranychidae. It was first described from speci- 
 mens taken from the upper surface of camphor leaves, Camphor a offici- 
 nale, in Florida. It has been recorded as feeding on the following plants : 
 eucalyptus, elm, willow, oak, and pecan. In California the writer has 
 collected specimens in San Diego, Orange, and Los Angeles counties. 
 
 Nature of Injury. — The avocado brown mite confines its feeding en- 
 tirely to the top surface of the leaf. The first evidences of brown mite 
 work are the pale white spots that are scattered over the green leaf sur- 
 face. These represent the feeding places of the mites and are caused by 
 the actual removal of the green matter or chlorophyll from the leaf. As 
 the mites become more and more numerous, practically all of the green 
 
Bul. 592] Avocado Insects and Mites 33 
 
 matter is removed, leaving the leaf entirely brown. Restoration from 
 this type of injury is rapid if the mites are destroyed before the leaves 
 are too seriously injured. However, such injured leaves fall prema- 
 turely, causing in some cases a heavy defoliation. 
 
 Life History. — The egg of this mite (fig. 24, a and b) is a flattened 
 sphere with a prominent stalk. In height, this stalk is about twice the 
 diameter of the egg. Small threads seem to support the egg around the 
 base. Just after the egg has been laid it is pale yellow, but within a day 
 turns to a dark reddish brown. The average number of eggs laid by a 
 single female mite is about 35. The incubation period varies from 7 to 
 10 days, according to climatic conditions. 
 
 When the egg hatches it splits into halves in an even line around the 
 equatorial zone. After the larva works its way out of the egg the two 
 halves of the eggshell spring back into place again. The larva (fig. 24c) 
 is pale yellow and has but three pairs of legs, the fourth pair being ac- 
 quired after the first molt. Almost immediately after hatching the larva 
 begins to feed, sucking the coloring from the leaf. The larval stage lasts 
 from 2 to 3 days. 
 
 The first-stage nymph (fig. 24<:/) is similar to the larva except that it 
 is somewhat larger and possesses an additional pair of legs, and the body 
 is darker. This stage lasts from 2 to 3 days, during which time another 
 molt occurs. 
 
 The second-stage nymph (fig. 24e) is almost identical with the first- 
 stage nymph except that it is somewhat larger and of a darker reddish 
 brown. This stage lasts from 2 to 3 days, when the nymph molts and be- 
 comes the adult mite. 
 
 The adult of the avocado brown mite (fig. 24/) is a rusty red or choco- 
 late color. The body of the female mite is robust and oval, while the male 
 is narrower and pointed posteriorly. The total length of the life cycle of 
 this insect from egg to adult is approximately one-half month in sum- 
 mer at Encinitas. There are many generations produced in one season. 
 
 Dispersal. — The brown mites are very active and are capable of trav- 
 eling considerable distances through their own powers of locomotion. As 
 a general rule, however, they remain throughout their life on the same 
 leaf or closely adjoining ones. Mites are occasionally observed on the 
 ground, but they do not breed there. Leaves bearing colonies of mites 
 frequently fall or are blown to the ground by the wind. Perhaps the 
 greatest factor in the dispersion of the avocado brown mite is wind, 
 either carrying the individual mite or a leaf bearing a colon'y of them. 
 Birds, insects, and man are also undoubtedly responsible for the dis- 
 persion of small numbers of mites. 
 
34 University of California — Experiment Station 
 
 Predators. — The avocado brown mite, exposed as it is on the upper 
 surface of the leaves, is subject to the attacks of several enemies. Those 
 enemies are the same as attack the citrus red spider. 11 
 
 Control. — Sulfur, applied at full strength, is satisfactory in control- 
 ling" the brown mite on avocado. Since the leaf is free from excessive 
 webbing in the case of the avocado brown mite, the sulfur may be 
 brought into intimate contact with the mites. Along the coastal areas, 
 where the mite is most abundant, one or two applications, sometimes 
 followed by a spotted application, are usually effective in controlling 
 the mites. The sulfur should be applied when there is little wind. 
 
 Fig. 25. — Adult greenhouse thrips, Heliothrips haemorrhoi- 
 dalis (Bouche). (After Eussell, United States Department of 
 Agriculture.) 
 
 GREENHOUSE THRIPS 
 
 The greenhouse thrips, Heliothrips haemorrhoidalis (Bouche), is a pest 
 in many parts of the United States. It also occurs in Europe, Asia, and 
 the South Sea Islands. In western North America, it is most often found 
 outdoors on ornamental trees and shrubs. It is omnivorous in its feeding 
 habits. 
 
 Description,. — The greenhouse thrips (fig. 25) may be characterized 
 by the reticulated surface, very dark brown to almost black, and eight- 
 jointed antennae. 
 
 Nature of Injury. — Injury is caused to both the fruit and the leaves 
 of the avocado. Injury to the leaves consists of rasping and puncturing 
 
 ii For an account of predators on the citrus red spider, consult : Quayle, H. J., Biol- 
 ogy and control of citrus insects and mites. California Agr. Exp. Sta. Bui. 542:10-13. 
 
 
Bul. 592] 
 
 Avocado Insects and Mites 
 
 35 
 
 minute areas of the surface or epidermis and sucking out the chlorophyll, 
 which results in a bleached appearance. Large areas, sometimes covering 
 practically the entire leaf (fig. 26), may take on a silvery or bleached 
 appearance in the case of a severe infestation. This injury subsequently 
 results in the drying up and falling of the leaves. Injury to the fruit is 
 
 
 i ■ ' ; tf >•;■ , " 
 
 £'}y?i 
 
 . 
 
 Hyp, • ■•* 
 
 f 
 
 
 
 
 Fig. 26. — Typical avocado-leaf injury as caused by 
 the greenhouse thrips. 
 
 caused by the insects rasping off the surface of the skin. A green fruit 
 that has been seriously attacked by this thrips will ultimately acquire 
 a brownish appearance as a result of the extraction of chlorophyll. As a 
 result of this injury the affected areas become russety and deep cracks 
 may develop as the fruit increases in size. 
 
 Control. — A highly refined light medium oil, of a viscosity of 70 sec- 
 onds, may be used at 1% per cent with 1 pint of nicotine sulfate plus 1 
 pound of casein spreader to 100 gallons of diluted spray. Two applica- 
 tions may be necessary, with an interval of 2 or 3 weeks. 
 
 BROAD-NOSED GRAIN WEEVIL 
 
 The broad-nosed grain weevil, Caulophilus latinasus Say, was first re- 
 corded in California in October, 1927, by A. A. Brock, at that time 
 
36 
 
 University of California — Experiment Station 
 
 Agricultural Commissioner of Orange County. Since then it has spread 
 rather generally throughout the state. 
 
 Distribution and Hosts. — According" to the literature, this species is 
 limited in its distribution and it is unlikely that it is cosmopolitan. It has 
 been recorded from the West Indies, Georgia, South Carolina, Jamaica, 
 
 Fig. 27. — Larvae and pupae of the broad-nosed 
 grain weevil, Caulophilus latinasus Say, in the 
 seed of an avocado. Note holes made by the lar- 
 vae. (Slightly enlarged.) 
 
 Puerto Rico, Mexico, Guatemala, and Madeira. Avocado seeds are ap- 
 parently the primary host of this species in California. Other known 
 hosts are chickpeas, Indian corn, and ginger. 
 
 Description and Habits. — Superficially this species resembles the 
 granary weevil, Sitophilus granarius (Linn.) (Calandra granaria 
 Linn.), except that it is a darker brown. It belongs to the same family, 
 Calandridae of the Rhynochophora. 
 
 The attacks of the broad-nosed grain weevil on avocado may be con- 
 sidered of secondary importance. It attacks fallen fruits, boring 
 through the rotting flesh and entering the seed (fig. 27) . No fruit, while 
 on the tree, has as yet been found attacked by this species. 
 
Bul. 592' 
 
 Avocado Insects and Mites 
 
 37 
 
 FALSE CHINCH BUG 
 
 The false chinch bug, Nysius ericas (Schilling), is a light or dark-gray 
 species, measuring approximately % inch in length. The nymph is pale 
 gray with reddish-brown abdomen, resembling the dry weeds and soil to 
 a remarkable degree. This species breeds and feeds primarily in the 
 native grasslands. In September and October, and again in May and 
 June, the wingless nymphs swarm from the dry grasslands into adjoin- 
 ing avocado groves and infest primarily the smaller trees, causing con- 
 siderable damage. After the spring swarming, maturity is reached and 
 eggs are laid in cracks in the soil or on grass and weeds. There are from 
 four to seven generations a year. The winter may be passed in the egg, 
 nymph, or adult stage. Control measures consist of burning over or cul- 
 tivating the adjoining grasslands; or dusting with 25 per cent calcium 
 cyanide, or very strong nicotine dust. 
 
 AVOCADO PESTS OF LESSER IMPORTANCE 
 IN CALIFORNIA 
 
 The following species may be frequently seen on avocados in Califor- 
 nia, but are not generally of sufficient economic importance to warrant 
 efforts at control. They are listed according to order and family. 
 
 Pseudococcus nipae Maskell, palm 
 
 mealybug 
 Saissetia hemisphaerica (Targ.), hemi- 
 spherical scale 
 Hemiptera, Pentatomidae : 
 
 Murgantia Mstrionica (Halm), harle 
 quin cabbage bug 
 Coleoptera, Chrysomelidae : 
 
 Diabrotica soror Lee, western twelve- 
 spotted cucumber beetle 
 Diabrotica balteata Lee, belted cu- 
 cumber beetle 
 Coleoptera, Bostrichidae : 
 
 Polycaon confertus Lee, olive twig 
 borer 
 Lepidoptera, Gracilariidae : 
 
 Marmara sp., avocado fruit and twig 
 miner 
 Lepidoptera, Noctuidae : 
 
 Heliothis obsoleta Fabr., corn earworm 
 Lycophotia margaritosa (Haworth), 
 variegated cutworm 
 
 Corrodentia, Psocidae : 
 
 Bark lice (species undetermined) 
 Homoptera, Aphididae : 
 
 Doralis (Aphis) gossypii (Glover), 
 melon or cotton aphids 
 Homoptera, Coccidae : 
 
 Ceroplastes cirripediformis Comst., 
 barnacle scale 
 
 Ceroplastes cistudiformis Towns, and 
 Ckll. 
 
 I eery a purchasi Maskell, cottony cush- 
 ion, or fluted, scale 
 
 Lecanium corni Bouche, brown apricot 
 scale 
 
 Phenacoccus colemani Ehrh., Mexican 
 mealybug 
 
 Pseudococcus citri (Risso), citrus 
 mealybug 
 
 Pseudococcus galiani Green, citrophi- 
 lus mealybug 
 
 Pseudococcus longispinus (Targ.), 
 long-tailed mealybug 
 
 Pseudococcus maritimus (Ehrh.), Ba- 
 ker's or grape mealybug 
 
38 
 
 University of California — Experiment Station 
 
 AVOCADO PESTS OF THE WORLD 
 
 The following list of insects attacking the avocado in other states and 
 countries has been compiled for the use of entomologists. The records are 
 submitted here in order that the foreign species be known and that 
 such action can be taken as may be necessary in case any are intercepted. 
 
 AFRICA 
 
 Thysanoptera, Thripidae : 
 
 Selenothrips (Heliothrips) rubrocinc- 
 tus Giard. 
 Homoptera, Coccidae: 
 
 Ceroplastes floridensis Comst. 
 
 Chrysomphalus dictyospermi (Morg.) 
 
 Pulvinaria pyriformis Ckll. 
 
 Saissetia perseae Brain 
 Hemiptera, Coreidae : 
 
 Homoeocerus sp. 
 
 Hemiptera, Miridae: 
 
 Helopeltis sp. 
 Coleoptera, Bostrychidae : 
 
 A pate terebrans Pall. 
 
 A pate monacha Fabr. 
 Coleoptera, Oerambycidae 
 
 Batoeera rubus Linn. 
 Lepidoptera, Cossidae : 
 
 Zeusera eoffeae Nietn. 
 
 BERMUDA 
 
 Acarina, Tetranyehidae : Paratetrariychus sp. 
 
 CENTRAL AMERICA 
 
 Homoptera, Coccidae : 
 
 Chrysomphalus scutiformis (Ckll.) 
 Coleoptera, Cucujidae: 
 
 Cathartus advena (Waltl.) 
 
 Coleoptera, Curculionidae : 
 
 Sitophilus (Calandra) oryza (Linn.) 
 
 Canal Zone 
 
 Homoptera, Coccidae: 
 Ceroplastes sp. 
 
 Ischnaspis longirostris (Sign.) 
 Pulvinaria pyriformis Ckll. 
 Saissetia hemisphaerica (Targ.) 
 Targionia biformis Ckll. 
 
 Homoptera, Aleyrodidae : 
 
 Aleurocanthus woglumi (Ashby) 
 
 Coleoptera, Curculionidae : 
 Heilipus perseae Barber i: 
 Pagiocerus rimosus Eich. 
 
 Lepidoptera, Xyloryctidae : 
 Stenoma catenifer Wlsm. 
 
 Lepidoptera, Saturniidae: 
 Hylesia sp. 
 
 Costa Rica 
 
 Coleoptera, Curculionidae : 
 Heilipus pittieri Barber 
 
 Lepidoptera, Pyralidae : 
 
 Stericta albifasciata (Druce) 
 
 12 Heilipus perseae is a very destructive avocado fruit weevil. For further infor- 
 mation regarding this insect, see Dietz and Barber (1920). 
 
Bul. 592] 
 
 Avocado Insects and Mites 
 
 39 
 
 Guatemala 
 
 Homoptera, Chermidae : 
 
 Trioza Tcoebelei Kirkaldy 
 Homoptera, Aphididae: 
 
 Doralis (Aphis) gossypii (Glover) 
 Homoptera, Coccidae: 
 
 Aspidiotus lataniae Sign. 
 
 Aspidiotus subsimilis Ckll. 
 
 Ceroplastes sp. 
 
 Chrysomphalus dictyospermi (Morg.) 
 
 Chrysomphalus perseae (Comst.) 
 
 Chrysomphalus personatus (Comst.) 
 
 Chrysomphalus scutiformis (Ckll.) 
 
 Coccus sp. 
 
 Diaspis boisduvalii Sign. 
 
 Biaspis sp. 
 
 Lecanium sp. 
 
 Lepidosaphes mimosarum (Ckll.) 
 
 Pseudoparlatoria ostreata Ckll. 
 
 Pulvinaria floccifera (Westw.) 
 
 Solenococcus sp. 
 Cbleoptera, Curculionidae : 
 
 Caulophilus latinasus Say 
 
 Conotrachelus perseae Barber 13 
 Diptera, Trypetidae: 
 
 Ceratitis capitata (Wied.) 
 Lepidoptera, Xyloryctidae : 
 
 Stenoma sp. 
 
 Honduras 
 Thysanoptera, Thripidae : Liothrips perseae Watson 
 
 Salvador 
 Diptera, Trypetidae: Anastrepha serpentina Wied. 
 
 EAST INDIES 
 
 Dutch East Indies 
 
 Lepidoptera, Lasiocampidae : 
 Suana concolor Walker 
 
 Diptera, Trypetidae: 
 
 Ceratitis capitata (Wied.) 
 
 ENGLAND 
 
 Homoptera, Coccidae: Pseudococcus maritimus (Ehrh.) (in greenhouses) 
 
 FIJI ISLANDS 
 
 Homoptera, Coccidae: Aspidiotus destructor Sign. 
 
 FRANCE 
 
 Homoptera, Coccidae: Aspidiotus lataniae Sign.; Aspidiotus palmae Morg. and Ckll. 
 
 GUAM 
 
 Coleoptera, Chrysomelidae : Phytorus (Rhyparida) pinguis Baly 14 
 
 13 Conotrachelus perseae is a serious seed pest which often discolors the flesh of the 
 fruit, thus rendering it inedible. For further information regarding this species, see 
 Popenoe (1919). 
 
 14 Specimens of this species were sent to the author by J. W. Dale, who was sta- 
 tioned in Guam from 1933-35. 
 
40 
 
 University of California — Experiment Station 
 
 HAWAIIAN ISLANDS 
 
 Homoptera, Coccidae: 
 
 Aspidiotus persearum Ckll. 
 
 Pseudococeus nipae Mask. 
 Homoptera, Aleyrodidae : 
 
 Aleurocanthus woglumi (Ashby) 
 Coleoptera, Scolytidae : 
 
 Crossotarsus externedentatus Fairm. 
 
 Hypothenemus eruditus Westw. 
 
 Xyleborus immaturus Blaekb. 
 
 Diptera, Trypetidae: 
 
 Ceratitis capitata (Wied.) 
 
 Dacus (Chaetodacus) xanthodes Broun 
 Lepidoptera, Xyloryctidae : 
 
 Stenoma catenifer Wlsm. 
 Lepidoptera, Tortricidae: 
 
 Amorbia emigratella Busck 
 
 INDIA 
 
 Lepidoptera, Cossidae: Zeuzera coffeae Nietn. 
 
 Ceylon 
 
 Coleoptera, Cerambyeidae : 
 
 Batocera rubus Linn. 
 
 Crocercops ordinatella Meyr. 
 Coleoptera, Scolytidae : 
 
 Xyleborus fornicatus Eieh. 
 
 Lepidoptera, Tortricidae : 
 Homona coffearia Nietn. 
 
 Lepidoptera, Cossidae : 
 Zeuzera coffeae Nietn. 
 
 JAPAN 
 
 Homoptera, Coccidae: Aspidiotus persearum Ckll. 
 
 MEXICO 
 
 Homoptera, Coccidae : 
 
 Ceroplastes cistudiformis Towns, and 
 Ckll. 
 
 Clirysomphalus scutiformis (Ckll.) 
 
 Icerya montserratensis Riley and How- 
 ard 
 Homoptera, Chermidae: 
 
 Trioza ~koebelei Kirkaldy 
 Hemiptera, Membracidae : 
 
 Hopolphora mono gramma Germar 
 
 Coleoptera, Curculionidae : 
 
 Conotrachelus aguacatae Barber 
 
 Heilipus lauri Bob. 
 Lepidoptera, Xyloryctidae : 
 
 Stenoma catenifer Wlsm. 
 Lepidoptera, Pyralidae : 
 
 Stericta aloifasdata (Druce) 
 
 PHILIPPINE ISLANDS 
 
 Homoptera, Coccidae : 
 
 Drosicha contr aliens Walker 
 Saissetia formicarii (Green) 
 
 Hemiptera, Miridae : 
 
 Helopeltis antonii Watrb. 
 
 Coleoptera, Scarabaeidae: 
 Euelea capito Pasc. 
 Niplionoclea (Euelea) albata Newm. 
 
 Diptera, Trypetidae 
 
 SAMOA 
 
 Dacus (Chaetodacus) xanthodes Broun 
 
Bul. 592 
 
 Avocado Insects and Mites 
 
 41 
 
 SOUTH AMERICA 
 
 Brazil 
 
 Thysanoptera, Thripidae : 
 
 Selenothrips (Heliothrips) rubrocinc- 
 tus Giard. 
 
 Homoptera, Coccidae : 
 
 Aspidiotus destructor Sign. 
 Aspidiotus lataniae Sign. 
 Chrysomphalus personatus (Comst.) 
 Chrysomphalus scutiformis (Ckll.) 
 Ischnaspis longirostris (Sign.) 
 Platinglisia noacTci Ckll. 
 Pseudaonidia trilobitiformis (Green) 
 Saissetia hemisphaerica (Targ.) 
 
 Homoptera, Aleyrodidae : 
 
 Aleurotrachelus sp. 
 
 Aleyrodes insignis Bondar 
 Coleoptera, Cerambycidae : 
 
 Acanthoderes jaspidea Germar 
 
 Oncideres sp. 
 Lepidoptera, Xyloryctidae : 
 
 Stenoma catenifer Wlsm. 
 Lepidoptera, Pyralidae : 
 
 Stericta albifasciata (Druce) 
 
 Thysanoptera, Thripidae : 
 
 Heliothrips haemorrhoidalis (Bouche) 
 Homoptera, Coccidae: 
 
 Aspidiotus destructor Sign. 
 
 Chile 
 
 British Guiana 
 
 Chrysomphalus personatus (Comst.) 
 Pulvinaria pyriformis Ckll. 
 
 Homoptera, Coccidae : is 
 
 Pseudococcus gahani Green 
 
 Saissetia oleae (Bernard) 
 Thysanoptera, Thripidae : 
 
 Heliothrips haemorrhoidalis (Bouche) 
 
 Coleoptera, Curculionidae : 
 Pagiocerus rimosus Eich. 
 
 Lepidoptera, Psychidae : 
 
 TJianatopsyche chilensis Phil. 
 
 Ecuador 
 Lepidoptera, Pyralidae : Stericta albifasciata (Druce) 
 
 French Guiana 
 Lepidoptera, Pyralidae: Stericta albifasciata (Druce) 
 
 Paraguay 
 Coleoptera, Cerambycidae : Oncideres fasciatus Lucas 
 
 Peru 
 Lepidoptera, Pyralidae : 
 
 Stericta albifasciata (Druce) 
 
 SPAIN 
 
 Homoptera, Coccidae : Icerya montserratensis Riley and Howard 
 
 TAHITI 
 
 Coleoptera, Nitidulidae : Carpophilushemipterus (Linn.) 
 
 Hymenoptera, Formicidae 
 Atta sexdens Linn. 
 
 is Through the courtesy of H. Compere, information regarding these two species of 
 scale insects, both of which are apparently new records, was made available. Of the 
 two species, Pseudococcus gahani is the major pest of the avocado in Chile. 
 
42 
 
 University of California — Experiment Station 
 
 UNITED STATES OF AMERICA^ 
 
 Florida 
 
 Thysanoptera, Thripidae : 
 
 FranMiniella cephalicus Craw. 
 FranMiniella cephalicus var. bruneri 
 
 Watson 
 FranMiniella cephalicus var. masoni 
 
 Watson 
 Heliothrips haemorrhoidalis (Bouche) 
 Selenothrips (Heliothrips) rubrocinc- 
 
 tus Giard. 
 Homoptera, Cicadellidae ( Jassidae) : 
 
 Empoasca minuenda Ball 
 Homoptera, Coccidae : 
 Aspidiotus camelliae Sign. 
 Aspidiotus cyanophylli Sign. 
 Aspidiotus hederae (Vallot) 
 Aspidiotus lataniae Sign. 
 Aspidiotus orientalis cocotiphagus 
 
 (Marlatt) 
 Ceroplastes floridensis Comst. 
 Chrysomphalus agavis (Towns, and 
 
 Ckll.) 
 Chryso7nphalus aonidum (Linn.) 
 Chrysomphalus dictyospermi (Morg.) 
 Chrysomphalus perseae (Comst.) 
 Coccus hesperidum Linn. 
 Fiorinia fioriniae (Targ.) 
 Hemichionaspis minor (Mask.) 
 Hemichionaspis sp. 
 Pseudaonidia articulatus (Morg.) 
 Pseudischnaspis alienus (Newstead) 
 Pseudococcus citri (Risso) 
 Pseudococcus longispinus (Targ.) 
 Pseudococcus maritimus (Ehrh.) 
 Pseudococcus nipae Mask. 
 
 Mary 
 
 Acarina, Tetranyehidae : Oligonychus major Ewing 
 
 Pseudococcus virgatus (Ckll.) 
 
 Pulvinaria psidii Mask. 
 
 Pulvinaria pyriformis Ckll. 
 
 Saissetia hemisphaerica (Targ.) 
 
 Saissetia oleae (Bernard) 
 
 Tetralecia sp. 
 Homoptera, Aleyrodidae : 
 
 Aleurocanthus woglumi (Ashby) 
 
 Paraleurodes perseae Quaint. 
 
 Trialeurodes floridensis (Quaint.) 
 Hemiptera, Pyrrliocoridae : 
 
 Dysdercus suturellus H. and S. 
 Hemiptera, Tingidae: 
 
 Acysta perseae Heid. 
 C'oleoptera, Scarabaeidae : 
 
 Anomala undulata Mels. 
 Coleoptera, Cerambycidae : 
 
 Elaphidion inerme Newm. 
 
 Lypsinena fuscata Lee. 
 Coleoptera, Cureulionidae : 
 
 Araeocerus fasciculatus DeG. 
 
 Caulophilus latinasus Say 
 
 Conotrachelus serpentinus Boh. 
 
 (Cryptorhynchus) Apteromechus fer- 
 ratus (Say) 
 Lepidoptera, Noctuidae : 
 
 Sparganothis sp. 
 
 Xylomyges eridania Cram. 
 Lepidoptera, Gracilariidae : 
 
 Gracilaria perseae Busek 
 
 Gracilaria violacella Clem. 
 Acarina, Tetranyehidae : 
 
 Paratetranychus yothersi McG. 
 
 LAND 
 
 Homoptera, Coccidae : 
 
 Aspidiotus destructor Sign. 
 Ceroplastes floridensis Comst. 
 Chrysomphalus dictyospermi (Morg.) 
 Icerya montserratensis Eiley and How 
 ard 
 
 WEST INDIES 
 
 Pulvinaria pyriformis Ckll. 
 Saissetia hemisphaerica (Targ.) 
 Saissetia nigra (Nietn.) 
 Saissetia oleae (Bernard) 
 Selenaspidus articulatus (Morg.) 
 Targionia biformis (Ckll.) 
 
 16 Localities discussed under this heading do not include California. See preceding 
 sections of bulletin. 
 
Bul. 592] 
 
 Avocado Insects and Mites 
 
 43 
 
 Coleoptera, Bostrychidae : 
 Apate monacha Fabr. 
 
 Coleoptera, Cerambycidae : 
 Batocera rubus Linn. 
 
 Coleoptera, Curculionidae : 
 Diaprepes abbreviatus Linn. 
 
 Lepidoptera, Megathymidae : 
 Calpodes ethlius Cram. 
 
 Barbados 
 
 Isoptera, Termitidae: 
 
 Constrictotermes incisus Snyder 
 Homoptera, Coccidae : 
 
 Chrysomphalus dictyospermi (Morg.) 
 
 Pseudococcus nipae Mask. 
 
 Pulvinaria pyriformis Ckll. 
 
 Coleoptera, Curculionidae : 
 
 Diaprepes abbreviatus doublieri 
 
 Guerni 
 Diaprepes sprengleri Linn. 
 
 Lepidoptera, Cossidae: 
 
 Duomitus punctifer Hamp. 
 
 Cuba 
 
 Thysanoptera, Thripidae : 
 
 FranTcliniella cephalicus bruneri Wat- 
 son 
 
 FranJcliniella tritici (Fitch) 
 
 Heliothrips haemorrhoidalis (Bouche) 
 Homoptera, Coccidae: 
 
 Aspidiotus destructor Sign. 
 
 Toumeyella sp. 
 Homoptera, Aleyrodidae : 
 
 Aleurocanthus woglumi (Ashby) 
 
 Coleoptera, Bostrychidae : 
 
 Apate carmelita Fabr. 
 Coleoptera, Curculionidae : 
 
 Pachnaeus litus (Germar) 
 Coleoptera, Scolytidae : 
 
 Pagiocerus rimosus Eich. 
 Lepidoptera, Bombycidae : 
 
 Oiketicus poeyi Lucas 
 Hymenoptera, Formicidae : 
 
 Atta insularis Guerni 
 
 Puerto Rico 
 
 Isoptera, Termitidae : 
 
 Nasutitermes (Eutermes) morio Latr. 
 Homoptera, Cicadellidae : 
 
 Empoasca minuenda Ball 
 Homoptera, Coccidae : 
 
 Aspidiotus destructor Sign. 
 
 Coleoptera, Scarabaeidae : 
 
 Lachnosterna (Phyllophaga) sp. 
 
 Coleoptera, Curculionidae : 
 Diaprepes abbreviatus Linn. 
 
 Saint Thomas 
 
 Homoptera, Coccidae: Aspidiotus articulatus (Morg.) ; Aspidiotus palmae Morg. and 
 Ckll. 
 
 Trinidad and Tobago 
 
 Thysanoptera, Thripidae : 
 
 Heliothrips haemorrhoidalis (Bouche) 
 
 Selenothrips (Heliothrips) rubrocinc- 
 tus Giard. 
 Homoptera, Coccidae: 
 
 Aspidiotus destructor Sign. 
 
 Pseudococcus citri (Risso) 
 
 Pseudococcus nipae Mask. 
 
 Pulvinaria pyriformis Ckll. 
 
 Saissetia nigra (Nietn.) 
 Homoptera, Aleyrodidae : 
 
 Aleurodicus neglectus Quaint. 
 Lepidoptera, Pyralidae : 
 
 Stericta albifasciata (Druce) 
 Hymenoptera, Formicidae : 
 
 Solenopsis geminata (Fabr.) 
 
 Virgin Islands 
 Coleoptera, Cerambycidae: Batocera rubus Linn. 
 
44 University of California — Experiment Station 
 
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