These articles are written to apply to the northeastern
corner of Illinois. Problems and timing may not apply outside of this
area. |
Early Fall Color on Trees & Shrubs
August 13, 1998
With August nearly half gone, thoughts are already turning to school
resuming and fall right around the corner. When shade trees start turning
fall color early, are they just anticipating things ahead or having some
kind of problem? Unfortunately, trees turning in late August most likely
are stressed or in decline. Take some time to check these problem trees
out.
While the color shows up in the canopy, start your inspection by looking
down to the base of the tree. Root zones are key areas. Root damage is
a very common stress factor that can lead to early fall color and decline.
Types of damage may include direct injury from digging near the tree,
injury from soil fill placed over the root zone, chemicals in the soil,
excess water, or too little water. In addition, consider a girdling root
to be a possibility, as roots growing across others or cutting into the
trunk can be a serious problem.
Pay attention to the very base of the trunk. There should be a natural
root flare in this location. If the trunk goes straight into the ground
like a telephone pole, problems are likely to occur. This situation may
be due to soil fill, girdling roots, or perhaps planting the tree too
deeply.
Many of these root problems offer little in terms of solutions. Girdling
roots can be cut after carefully digging away the soil. Most of the other
problems are preventable but little can be done once damage has occurred.
Examine trunks for wounds of various types, perhaps from equipment, storms,
winter damage, or animals. Since the "lifeline" of trees (sending up water
and nutrients) is just under the bark, damage to trunks can have significant
impact and may be why a tree is stressed and declining. Applying pruning
wound dressing to damaged trunk areas is not suggested.
Certainly the weather also can play a part in adding stress to trees.
Drought and severe winters can lead to tree decline; although neither
is a leading cause here in 1998, past seasons could still be an influence
on tree health. The best overall suggestion for stressed trees is to avoid further stress.
Water during drought periods, including fall. Perhaps fertilizing this
fall or next spring may help. Also prune out dead wood, but avoid heavy
pruning in late summer and early fall. |