Article By Woods Houghton

At times during the winter, particularly for evergreens, drying out can be a real problem. Especially when we have mild warm winters such as we are having this year. Winter drought occurs when a tree loses more water than it can absorb from dry ground and is especially acute during the early spring when we have received very little winter moisture, the spring sun begins warming the rest of the tree. Windy conditions can also worsen the problem. Even dormant trees need moisture to promote root growth and health.

Winter water needs are often overlooked or forgotten about. Trees and shrubs and even dormant Bermuda grass benefit from a good normal watering once a month December to March when it starts to warm up. By laying down a thick layer of organic mulch around the base of the tree in late fall before winter’s onset will help conserver water thru the winter and keeps the soil cool to help prevent winter injury. The mulch can help to slow moisture loss and runoff while acting as a temperature buffer for the roots. Signs of winter drought injury include early budding, tip die back and poor plant vigor.

For more information Contact your Local County Extension office. This and all programs are available to everyone regardless of age, color, disability, gender, national origin, race, religion, or veteran status. New Mexico State University, U.S. Department of Agriculture, and the Eddy County Government Cooperating “to put knowledge to work”.

This time of year I get lots of calls on trees and shrubs with the leaf edges burning back and veins and middle green but slowly browning. Most often occurs during hot weather, usually in July or August. Leaves turn brown around the edges and between the veins. Sometime the whole leaf dies, or a large number drop during the late summer. This problem is most severe on the youngest branches or new growth. Trees do not generally die and the twigs are supple and show signs of life. The leaf is often supple as well, which helps differentiate this from iron deficiency, salt burn and scorch mite. It happens often following a rain in Eddy county.

Leaf scorch is caused by excessive evaporation of moisture from the leaves. In hot weather, and low humidity water evaporates rapidly from the leaves. If the water has a high salt content such as found in South Eastern New Mexico salts may be left behind and some salt burn can occur as well. Salts also cause a physiological drought to the plant as well. If the roots cannot absorb and convey water fast enough to replenish this loss, the leaves turn brown and wither. This occurs in dry soil but if high salt concentration in the soil or water can occur under moist conditions as well. Other contributing factors include hot dry winds, limited soil area, or insufficient watering depth. Summer leaf scorch is more prevalent in trees and shrubs with shallow roots, such as sycamore, mulberry, cottonwoods, and some oaks.

To prevent further scorch deep-water trees during periods of hot weather to wet down the entire root space and proper location and planting of trees. Water less often but for longer periods of time will result in deeper rooting depth, less leaf scorching and reduced blow over of trees. The evaporation rate in Eddy County exceeds 110 inches per year, and in midsummer with temperature exceeding 100 degrees F. can exceed 2 inches per day. This can create a demand the exceeds the delivery capacity of the tree in simple words a two inch per day demand and the tree only has the physical capacity to deliver 1.75 inches. This can get further complicated by having two crops in the same location such as trees and a lawn, or trees and flowers. The grower needs to supply the water for both crops and in the hot dry weather this can be difficult.

For more information Contact your Local County Extension office. Eddy County Extension Service, New Mexico State University is an equal opportunity/affirmative action employer and educator. All programs are available to everyone regardless of race, color, religion, sex, age, handicap, or national origin. New Mexico State University, U.S. Department of Agriculture, and the Eddy County Government Cooperating.