Extension Communications
3614 Administrative Services Building
Ames, Iowa 50011-3614
(515) 294-9915
6/10/02
Contacts:
Paul H. Wray, Forestry, (515) 294-1168, phw@iastate.edu
Jean McGuire, Continuing Education and Communication Services, (515) 294-7033,
jmcguire@iastate.edu
Yard and Garden Column for the Week Beginning June 14
Make Your Trees “Smile”
By Paul Wray
Extension Forester
Iowa State University
Trees planted in our landscapes will perform better, look better, grow
better, and be “happier” if we treat them well and provide some
of their requirements and training for growth and function. Here are some
guidelines for those new trees in the landscape.
Watering is easy, but often done improperly. Watering slowly from above
is the best and most natural technique. Water regularly during the first
year after planting and if planting a large specimen, consider watering
during the second year. Water every 10-14 days, if natural rain has been
less than one inch. When you water, water slow and with sufficient quantity
to ensure that the entire root system is soaked. You cannot supply too
much water to the plant, but you can over water with respect to frequency.
By going 10-14 days between watering, root expansion is encouraged. By
watering too frequently, the roots may suffer from lack of oxygen and
root expansion does not keep up with top growth.
Fertilization is normally not required. If planting in a good Iowa soil,
more than enough nutrients are present and available for good tree establishment
and growth. If planting on disturbed sites, consider doing a simple garden
soil test to determine the fertility level of the tree planting site.
If general fertility is low, consider fertilizing with a balanced fertilizer
(such as 12-12-12) which will stimulate more root development than using
fertilizers high in nitrogen. Application to the soil surface is sufficient
in most cases; nutrients will become available to the tree’s root
system over time.
When planting, even on poor or disturbed sites, do not add amendments
such as peat or sphagnum moss. Replace the soil in the planting hole with
the same soil removed.
Use mulches when possible. Mulching around trees, improves the rooting
environment; temperature extremes are dampened and soil moisture is conserved
and retained during dry periods. As mulches decay, they are incorporated
into the soil, releasing nutrients, improving soil structure, and improving
almost all soil characteristics for tree growth. Wood chips and bark are
the preferred mulches because they will remain on the landscape longer
than fine mulches. When mulching, avoid placing mulch next to stem of
the tree and use 3-4 inches over as much of the root system of the tree
as possible. Over time, as the mulch is incorporated, refresh the mulch
around the tree with the addition of new mulch.
Without a doubt, the proper application of mulches is one of the best
cultural practices you can do for a tree or shrub to enhance growth and
vigor of the plant.
Pruning young trees and how they are pruned is a determinant in how long
and how well they perform in the landscape. Pruning is simple, with a
few important rules. When planting new trees, prune only to correct any
problems such as double multiple leaders, crossing branches or damaged
branches. Do not remove branches to try and correct for a root deficiency;
instead buy plants with good root systems. For the first 7-10 years of
life of a young tree, follow two simple pruning rules.
Rule 1: Correct multiple leaders as soon as you see them. Maintain a
single main stem on trees for as long as possible.
Rule 1a: Remove suckers forming at the base of the tree as soon as possible.
They do not contribute to growth of the tree.
Rule 2: For temporary side branches, remove them when they are between
one and two inches in diameter. These branches are good providers of food
for diameter and root growth of the tree; removing branches too early
does not allow for rapid growth or strong tree formation.
Make sure to use proper removal techniques when removing branches.
For details on how to give your trees the right care, contact your county ISU Extension Office and ask for Publication PM 1591, “Community Tree Planting and Care Guide” or download the publication at http://www.forestry.iastate.edu/ext/urban.html.
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ml: isugarden
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