Deer control – Lands For Nature: Hands-On Restoration Instruction & Collaboration

US Midwest Prairie, Savanna, Oak Woodland, Sedge Meadow,

February 12, 2023

Last revision: March 2023

Browsing and rubbing by deer are a serious challenge for restoration. Due to their high population levels they can devastate trees, especially oaks, as well as tasty herbaceous perennials, such as lilies, swamp saxifrage, et al.. An additional challenge is the public’s image of deer as adored symbols of nature. Hunting is often ineffective. Perimeter fencing is expensive to install and maintain.

Oak trees Browse–Fencing individual plants is a good option that is suitable for smaller scale plantings of up to a few hundred plants. Oaks often can tolerate some browsing, but this can set back their growth for years. Eventually some trees will bolt above browse height, but this can take 10+ years. For larger plantings, eg 2 acres or more, planting a large number of trees can spread out browsing so a few trees grow above browse height. This can be at a planting rate of 300-400 trees/ acre.

For lower density plantings or to allow for faster growth, tree protectors are used. The plastic protector tubes have two drawbacks—

They often melt during burns needed to establish prairies, savannas, and oak woodlands even if the immediate area is cleared. Radiant heat causes the plastic to “shrink wrap” onto the tree.
Oaks do best with a lot of light and they are slow to grow in height (they put reserves into root establishment and pest protection). Plastic tube restrict both the light and the seedling’s ability to spread out leaves for several years until they emerge from the tube top.

An alternative which has lead to faster growth and lower mortality is to use a cylinder of open fence. This involves cutting 5 ft lengths of five feet high rolled 2” x 4” metal mesh fencing typically 14ga galvanized. Each cut panel, 5ft x 5ft, is clipped together to make a cylindrical cage. To hold up a cage a 5 ft length of 1/2” galvanized electrical conduit (EMT) is pounded into the ground to a height of about 45” and the cage is clipped together with 3 split ring clips, 1 1/4 ” size. The cage is placed over the seedling with the 1/2”EMT passing through the clip rings. Cage set up. Advantages to this system is that the cages can be lifted off to allow replacement and pruning if needed. Cages and posts can be used again and again as trees grow above browse level. To remove the clips are removed and the cage unwrapped from the tree. Cage are not damaged if using a brush cutter or string whipper when prepping for a burn.

Material cost is low—buy fencing by the roll. Common mesh sizes are 2″ x 4″ or 4″ x 4″ 14 ga. EMT comes in 10 ft lengths which yield two posts. Cutting the fence roll to 5 ft lengths is quickly done by making a simple 58″ wide by 42″ high jig. Cut the fencing strands with a cable cutter works better than a wire or bolt cutter. Some people leave the cut stubs or others trim them off for smoother edges. The cut 5ft x 5ft segments can be stacked “flat”, then rolled together and clipped with a bungy cord. Each 5 pack bundle can be carried from tree to tree.

When planting, put the tree into the ground and press in one post about 14” from the tree in a standard direction from the tree eg NW. After planting, come back with a hammer/ 3 lb mallet, the clip rings, and the nested cages. Small seedlings can be hard to find. Setting the posts at a standard distance and direction helps and waiting for some leaves to develop also makes it easier to spot the seedlings. Seedlings do not need cages immediately and caging can be done as scheduling permits. Set the post to about a bit higher than waist height (45” or so), then clip the cage together with 3 split rings, place the cage above the tree and slip each clip ring over the post while lowering the cage. To prevent the cage from moving side to side in the wind, one or two weed barrier fabric pins can be place opposite the post (if using one pin) or 60 degrees from the post to make additional anchor points. A single post set about 45″ above ground can withstand the wind, at least in heavier soils.

Time for this method is as follows:

Cut ½ EMT posts into two 5 ft lengths by cutting a bundle of ten 10 ft pipes at once with a hacksaw or reciprocating saw. About 10 minutes to make 20 posts.
Unrolling the fencing. Starting with a 50 ft roll of fencing, roll the full length out. Weight the starting end with the jig, have a weight about 50 ft away, and unroll the fencing to the weight by standing to the fencing as you unroll it. Once unrolled used the weight to hold down the end. This takes about 5 minutes.
Cut the fence into 5 ft long panels. Align the jig edge on the uncut fence edge. Step on the jig to flatten the fencing, cut just past the jig leaving 2 uncut strands. While standing on the uncut fencing, cut the two skipped stands. Lift the jig off the cut panel and set it on the uncut fencing edge and repeat. To cut 10 panels takes about 7 minutes.
Nest 5 panels, then stand the nested panels and clip together with a bungy cord. About 4 minutes per bundle.
Setting the post and clipping the panel to form a cage takes about 3 minutes per tree.

Burning around caged trees. Prior to burning an circular area about 6 ft around each tree can be but as short as possible. A brush cutter with a flail cutting head works well. The cut material can be raked out or cut several months prior to burning to reduce fire creep. In situations with high flames spot lighting on each tree side of the cleared circle to create mini head fires can reduce radiant heating. This reduction of burn risk photo is from a low fuel burn.

Oak Tree Rub–Trees which are large enough to be above browse height and under 6″ diameter at breast height sometimes are used by deer as rub trees in the fall. An effective and inexpensive preventative approach is to “disguise” the tree with a short section of plastic tree protector. A length of about 2 ft is hung around the stem with rope from about 4 ft above ground Rub protector. Deer seem to ignore the trees with these protectors. Being loose and above ground they are less prone to melting when burning; however, mowing an area about 6 ft around the tree can be done.

Herbaceous perennials

The cage style described above can be used to protect lilies and other taller herbaceous perennials from deer. For smaller plants covered cages are another option.

For small patches it is more efficient to enclose then with 5 ft tall wire fencing (2″ x 4″ to 4″ x 4″) because deer are reluctant to hop into confining spaces. Using a 50 ft length a hexagon area with 8 ft sides has been used. This arrangement is about 165 sq ft. For access 3 short bungy cords hold one end closed. T-posts were used to add rigidity; however, the attachment wires can not be under tension. MORE UPDATES IN PROGRESS see Exclusion hexagon diagram and exclusion hexagon photo.

*Notes–Terms and abbrev: EMT is electrical metal tubing. Cable cutters work better than standard wire cutters or bolt cutters.