>Tv Division of Agricultural Sciences UNIVERSITY OF CALIFORNIA *r« ) CALIFORNIA AGRICULTURAL Experiment Station Extension Service CIRCULAR 514 To date, the most practical method of minimizing or controlling deer damage to high-value crops in Cali- fornia has been through the use of well constructed fences. Although initial costs are high and continuing maintenance is necessary, fencing is economically jus- tified for the protection of certain crops and for many orchards, vineyards, and irrigated pastures; fences can also be practical for new forest plantings. Two types of fence have proven most successful in California: the upright fence, and the slanting, or overhanging, fence. Electric fences are not generally satisfactory in the state, but may be useful under certain conditions. This circular discusses important factors to consider when planning and building fences. Ample illustrations of construction details are included. FENCES FOR CONTROLLIN WILLIAM M. LONGHURST MILTON B. JONES RALPH R. PARKS LOREN W. NEUBAUER MAYNARD W. CUMMINGS THE AUTHORS: William M. Longhurst is Associate Zoologist in the Experiment Station, Hopland Field Station; Milton B. Jones is Assistant Agronomist in the Experiment Station, Hopland Field Station; Ralph R. Parks is Agriculturist in the Agricultural Extension Service, Davis; Loren W. Neubauer is Associate Professor of Agricultural Engineering and Associate Agricultural Engineer in the Experiment Sta- tion, Davis; Maynard W. Cummings is Agriculturist in the Agricultural Extension Service, Davis. JUNE, 1962 [2] ? DEER DAMAGE Although many different methods for preventing or reducing deer damage to various agricultural crops, gardens, and areas of timber reproduction have been tried in California, only a few have had enough success to warrant recommenda- tion. Repellents, scare devices, and shoot- ing of deer under damage permits have all failed to give consistent relief, al- though in certain circumstances all of these methods may be useful in com- batting deer problems. Properly constructed fences generally give the only sure, lasting protection, it has been found. Even though the initial cost of installation of fencing is often high and continued maintenance is necessary, the expense can be justified economically in view of its effectiveness against damage that kungry deer can cause to high-value crops. Orchards, vineyards and irrigated pastures are the crops most frequently subject to depredation, though in many areas deer cause extensive damage to gar- dens or truck crops, and in timber-pro- ducing areas damage is widespread on young conifers, particularly when they are replanted. Damage results from deer eating or trampling the crops, but young trees may also be injured if bucks scrape them with their antlers. Under most circumstances the upright style of fence has proven most satisfactory but under some conditions the slanting fence is cheaper to construct and is ad- vantageous because of its lower height. Electric fences have not generally proven satisfactory in California, although some details of construction are provided in this publication. [3] Upright fences Variation in fence heights. While a height of 6 feet is usually adequate for upright fences on level ground, a 7-foot fence may be necessary against larger deer in the Sierra Nevada areas of Cali- fornia. Deer normally will not jump a 6- foot fence for food but if pressed they can jump an 8-foot fence on level ground. When fences are to be located on sloping ground, it may be necessary to build them 10 or 11 feet high to guard against deer jumping from above. Wire. Woven mesh wire is preferable for the full height of the fence; if econ- omy is necessary two or more strands of nine or ten gauge smooth wire can be stretched at 4 to 6 inch spacings above a 5-foot mesh. There is no advantage in using barbed wire for this purpose, and it is more costly. Welded mesh wire is less expensive than woven, but it is too rigid to conform readily to irregularities in the ground surface and is most useful on even ground. Wire lighter than 12% gauge is not recommended. Vertical stays should not be over 6 to 8 inches apart, and line wires not over 4 to 6 inches apart. Because deer will crawl under a fence when possible, mesh wire should be secured and kept close to ground level. An extra strand of barbed wire stretched along the ground will help prevent them from crawling under. In any depressions between posts, wire should be staked firmly to the ground or depressions should be filled with materials which will not deteriorate or wash away. A 3- to 4-foot piece of angle-iron post makes a good permanent stake to hold wire close to the ground. Posts. Wooden or steel posts may be used, the choice depending on availability and costs. Wooden posts are usually some- what cheaper, with sawed ones being more expensive than split posts. Their dimensions at the ends should not be less than 4 to 5 inches across. If fences are to be moved from time to time, steel posts are preferable because of the greater ease with which they can be installed and re- moved. Steel posts can be purchased in three types: T-shaped, channel, and angle. The T-type is more rigid and is perhaps preferable, with channel next and angle last in order of strength; prices also run in that order. Posts should generally be set about 10 to 12 feet apart, but extra posts may be necessary to hold the wire to the contour of uneven ground. When building with steel posts it is often advis- able to intersperse them with wooden posts in order to strengthen the fence — one wooden post for every three to five steel posts is the approximate ratio. Proper bracing along fence lines is im- portant to give sufficient strength. Wooden corner posts should be at least 6 inches across the ends and are prefer- able to steel posts unless the latter are set in concrete and are well braced. I2~ Ga. or larger wire mesh, 6 x6 mesh shown. 1 ' -*- T \ 1 » i I I I I I I LJ 2 Steel angle, 2 Pipe or wood Drawing at right shows end, gate, or general brace for normal deer fencing. Drawing below shows two methods of using wire, either mesh alone or combinations of mesh and smooth. Twisted no. 9wire Allowable mesh sizes. 4 , x4 ,, -6 ,, x8 ,, Possible mesh and smooth wire combinations a. T of mesh (as shown) b. 6' of mesh and 3 smooth wires (as shown) c. 5'of mesh and 6 smooth wires (not shown) 9-1 1 Ga. smooth wires. /< "Spacing I. z ■ - I — ! ;i i y. \U : $ ;;•;• V, IS (: ■. 1 1 % £ £ : •:' :';. : ! *?. i Si £ ; 1 1 1 u 3' or 12' 1 1 1 IV 1 1 1 I I LJ I I U 4" si" r» x4 Brace Method of con- structing corner brace for vertical deer fencing. An alternate method of construct- ing corner brace. Gates. With upright fences the gate height should be approximately equal to fence height. Weight should be kept to a minimum. A light wooden frame over which mesh wire is stretched is often sat- isfactory. If factory made aluminium gates are used, metal extensions may be bolted or welded on and mesh wire stretched over them. It is always advis- able to sink a metal or treated wooden base frame in the ground below the gate to give a uniform surface and to prevent deer from working under the gate. Overhanging or slanting fences Major advantages and disadvan- tages. This comparatively new type of fencing is cheaper to construct than up- right fencing because fewer and shorter posts are needed and lighter gauge wire can be used. Overhanging or slanting fences are particularly suitable for tem- porary fencing, as the few posts can easily be removed and the wire more readily rolled up. This type of fencing is also suit- able for locations where an upright fence would be unsightly or otherwise unsuit- able. The principal disadvantages of over- hanging or slanting fences are that cattle or horses can easily damage them, hogs are likely to push under them, and weeds growing underneath may render them in- effective unless controlled. The slanting fence is effective because it acts primarily as a psychological barrier to deer. Deer usually first try to crawl under such a fence and then, finding this impossible and with the wire extended above them, they are discouraged from jumping. For Panel gate which can be lifted aside. Frame of gate slightly longer than opening. Brace Hog rings Guy wire 2x4 to support gate Guy wire anchored to end stakes Stake Typical slanting deer fencing with panel gate. Gate support may be sunk into ground to provide sufficient anchor for the bottom guy wire. [7] Slanting deer fencing with vertical gate arrangement. Hog ring Guy wire this reason slanting fences are effective in one direction only. (See Basic design below.) Overhanging or slanting fences are not recommended when it is necessary to use minimum horizontal space. In heavy snowfall areas, mesh wire slanted at 45° or less is apt to be crushed down by the settling snow pack; smooth wires stretched horizontally at four-inch spac- ings are more useful in such circum- stances. Basic design. The slanting fence con- sists of approximately 6 feet of mesh wire supported by a guy wire stretched be- tween widely spaced posts. The drawings show such fences with different gates, and give construction details ; the high side of the fence is the side away from the area to be protected. Wire. For temporary installations, light chicken wire or stucco mesh may be used. For permanent installation, wire no lighter than 12% gauge is advisable. If woven wire is used, vertical stays should not be over 6 to 8 inches part and hori- zontal line wires should not be over 4 to 6 inches apart. Posts. Six-foot steel posts are recom- mended, spaced up to 30 to 40 feet apart. Gates. A hinged gate is needed if there will be considerable traffic. Ade- quate side wings should be provided. If little traffic is expected, a panel consist- ing of a light wooden frame with wire mesh stretched over it is often satisfac- tory. For easy access where no gate is needed, a stile is simple to construct. 9] Base board Drawing below shows stile for foot access over slanting fence. 2 x 4's of redwood or treated wood Pc4'x|2 I2-I4 0.C Slanting wire fence ^4'vr-o 1 or 8 L Can use f / similar stile for 25' PLAN VIEW Deer guard, or long cattle guard. [15] Drainage structures Where fences cross drainage channels it is necessary to guard against deer with out restricting water flow. If the channel is small, with an intermittent flow, some type of culvert is usually best. Such a culvert may be either a wooden box structure or a section of metal or concrete pipe. If a large, permanently flowing stream is to be spanned, swinging gates with the bottoms just below the surface of the water are effective. Swinging gate drainage structure. One or more 12-15" culverts or vertical pipes spaced not more than 6" apart maybe substituted for swinging gate. -) ^ 'fir*,. I ^ D 'o Q. 'a it works here . . . Many experiments conducted in the laboratories by staff members of the Division of Agricultural Sciences show promise of benefiting crops or animals. it may work here . . . Laboratory findings are often given further tests under controlled conditions in greenhouses (new plant varieties, for instance). ~:~:$ but will it work here? Possibly not. Some (these new plant varieties, for instance) fail miserably when the Experiment Station and Extension Service staff members collaborate in field testing the experiments. if it does ... if field tests indicate higher yields, greater resistance to pests or disease, drought or moisture — if the development benefits mankind, the facts will be made available. Thus is science applied to agriculture by the University of California • Division of Agricultural Sciences Co-operative Extension work in Agriculture and Home Economies, College of Agriculture, University of California, and United States Department of Agriculture cooperating. Distributed in furlhera-.ee of the Acts of Congress of May 8, and June 30, I'M 1. Ccorgc it. Alcorn, Director. California Agricultural Extension Service. 10w-6,'62(C8389)VL