1-2 is Spring 1992
Caring For Your Newly Planted Trees
Now that your trees have been successfully planted, what next? The care that you give your tree planting for the first three years will have a major bearing upon its ultimate success. Perhaps the most critical considerations during that time are: 1 ) weed control; and 2) animal damage control.
Controlling Weeds
Weed control should have begun at, or even prior to, the time of planting. If you planted into a field that was in crops the year before, no site preparation was really necessary. However, a light discing would have left an ideal planting condition if the site was not subject to erosion. If you planted into an old field where a cover of broadleaf weeds and grasses was already established, that vegetation should have been mowed closely, disced, or even sprayed with herbicide prior to planting.
Under any of these conditions a spot or band treatment of herbicide at
the time of planting is critical for good survival and early growth. Mowing alone
is not an acceptable alternative to herbicides. Most foresters feel that herbicide should
be applied at the time of planting, and for the next two years. An early spring
application is best, just about the time the young weeds are emerging. All herbicides
should be applied according to label directions. Rates will vary according to soil types.
Herbicide choice will depend upon the species of trees you have planted and your
particular weed problems. You should consult with a District Forester or Consulting
Forester licensed to apply herbicides, for specific suggestions as to the type and rate of
chemical to apply. Another excellent source of weed control are publications from Purdue
University. They conduct research every year on weed control in tree plantings. A
successful weed Control program in your new plantation is the single most important thing
you can do to get your trees off to a good start. A few plantings may experience some
unusual weed problems that call for spot treatments later in the season. Two examples are
Canada thistle and field bindweed. Not alt weeds can be controlled by a single application
of herbicide early in the season. If you discover a potentially serious weed problem later
in the growing season, consult someone about controlling it. Mulching and tilling are
alternatives to herbicide weed control. However, they are very time consuming and
considerably more expensive operations. One final note on weed control. It is not
practical or necessary to strive for completely weed-free conditions during the entire
season. If 75% of the weeds are controlled for a period of at least 60 days, you have been
successful. Most of the tree's growth takes place early in the growing season. A late
invasion of weeds will not severely hinder the survival or the growth of your seedlings.
If herbicides were applied at a rate that was heavy enough to provide season-long weed
control, there would be a high risk of damage to the trees themselves.
Controlling Animal Damage
It doesn't do any good to control the weeds in your planting if the deer, rabbits, or
mice eat all of your trees. Animal damage, especially from deer, is becoming a more
serious problem every year. While rabbits may do some damage to a planting, they are
seldom a serious threat. If you find a seedling that has been cleanly clipped off near
ground level that was probably done by a rabbit. Hunting, or live trapping on a smaller
scale, should adequate control if there is a problem.
Rodents, such as mice and voles, will sometimes girdle the base of the seedling by feeding
on the young bark. Fortunately this is not common. Rodent problems are more likely to
occur where weeds and grasses have not been well controlled. There are commercial
rodenticides available if you experience this problem. Without question, deer pose the
biggest threat to your planting: They will walk down a row of trees and browse the buds.
With white pine, they may strip the entire young seedling of its needles. Even though this
seldom kills the tree, the damage is severe. When the terminal bud (the one at the very
top of the tree) is destroyed, the tree loses its natural tendency to grow a single,
straight, central stem. A bushing effect often occurs when two or more lateral buds
compete for dominance. The end result is a low quality tree with multiple stems.
Research is being conducted on how to combat this deer problem. The two most common approaches are erecting a fence to keep the deer out, and spraying a material with a foul odor that repels the deer. Repellents are rather costly, and their effect is diminished after it rains. Conventional fencing is also costly but new alternatives with a high visibility electric fence look promising. Current research with fencing is aimed at developing unique and lower cost options.
For someone with just a few trees to protect, try hanging a small (hotel size) bar of soap
in some of the trees. Rain and dew will disperse an odor which is repugnant to deer. This
has worked successfully for several people. Others report that a dog left free to run
outside has kept the deer out of their planting. Allowing hunting is another method to
reduce deer numbers. Thankfully, deer are not a problem forever.
Once your trees get tall enough that the terminal bud is out of reach of the deer, any
browsing of the lower buds will not cause
serious harm.
Summary
You will not have a successful tree planting if you plant your
trees and forget them. Controlling weeds and animals, are keys to
getting your new planting off to a good start.
For further information or help with these problems contact
your Consultant or District Forester.