By Keith Mickler, County Coordinator and Agriculture Agent
It’s hot, its dry and its October; what the heck is up with this crazy hot weather. There has been hardly any quantifiable rainfall in almost four weeks. We sure could use some rainfall to help relieve our parched landscapes. With that being said let’s take a look into why water is so important to our trees and shrubs sheer existence.
Water is the single most important resource for tree and shrub survival. A water shortage severely damages our young and old trees/shrubs, and sets up our healthy ones with long-term issues. Think back to 2016 when Georgia experienced one of its worst droughts ever. Many of our trees are just now beginning to show signs of damage caused by the 2016 drought.
Drought conditions are leading to decline, pest problems, and non-recoverable damage. Supplemental watering will greatly help in maintaining tree health.
Many of our trees are old and valuable. They are considered non-replaceable beyond 10 inches in diameter. If these trees are damaged or lost to drought they cannot be replaced for several generations.
Manually, the best way to water our trees are with soaker hoses or trickle (drip) irrigation. Lawn irrigation systems are less efficient for applying water to trees than soaker hoses or drip irrigation, but are easy to use. Even a garden hose, moved often, can provide a good soil soaking.
Use mulch underneath the trees out to the drip-line to conserve moisture; apply water over the top of the mulch. Do not concentrate water at the base of the trunk as this can lead to other pest problems.
Most all of the tree’s absorbing roots are in the top foot of soil. Applying water deeper than this misses the most active roots and allows water to go unused and wasted. Apply water across the surface and let it soak into the soil. Surface soaking allows a tree’s roots more opportunity to absorb the water.
Lay water hoses or applicators out to the tree drip-line. Try to water the soil areas directly beneath the foliage and shaded by the tree. Do not water closer than 3 feet to the trunk on established trees. Be sure the water soaks in well. Make sure you use mulch and slow application rates on slopes, clays, and compacted soils to assure the water is soaking into the soil and not running off.
Do not spray tree foliage when applying water. Water droplets on tree leaves can lead to pest problems and destruction of leaf tissue through sun damage. Try not to wet the trunk if possible.
Young, newly planted trees need additional watering care. You must apply water directly over where you need it in the soil. For new trees, concentrate water over the root ball, as well as the planting area, to assure survival. Old, large trees should be extensively watered over the entire area under their foliage.
The best time to water is at night from 10 pm to 8 am. Trees replenish their water deficits during the night time hours. Watering at night allows full use of the water and not as much loss to evaporation.
Depending upon your soil type, daily temperatures, and rainfall amounts, 1-3 inches of water per week should keep a tree healthy. Trees in limited rooting areas such as containers or on major slopes need additional care to assure water is reaching the roots in sufficient amounts.
A little over ½ gallon per square foot equals 1 inch of water. To make this easy, say the area underneath the canopy of your tree is 1,000 square feet, then you will need to apply a minimum of 500 gallons of water evenly underneath the canopy to equal 1 inch of water. This might need to be done 2 to 3 times per week, all depends on rainfall and this miserably hot weather.
Trees should be watered once or twice a week (at least 1 inch of water per application) during the growing season if there is no rainfall in that particular week. One heavy watering is much better than many light, shallow watering’s. A bigger percentage of the water is used by the tree when watered heavily. Also, light watering encourages shallow rooting which can lead to even more severe drought damage.
Heck, we, me, all of us need to provide some extra water for our trees until mother nature starts to provide some herself if we wish to help our trees survive long term.
Keith Mickler is the County Coordinator and agriculture agent for The University of Georgia/Floyd County Cooperative Extension. Located at 12 E. Fourth Ave., Rome, GA 30161 (706) 295-6210. Office hours are Monday-Friday from 8 a.m. to 5 p.m.