Several Possible Causes for White Wheat Heads

Nearly every year wheat growers of this area report white heads, sometimes in alarming numbers. For this area of the state, a majority of the problem is caused by the wheat stem maggot which invades the stem cutting off nutrients to that part of the plant above the location of the maggot. An easy test for the presence of the maggot is to gently pull on the affected stem. If it comes out with just slight resistance the bottom of the removed stem will have a brown discoloration and evidence of chewing by the maggot.

Given this year's unusual heat and dry conditions one should not rule out other reasons for the white heads. These include root rot, sterility, scab, barley yellow dwarf and even herbicides.

Root rot is usually characterized by the heads of the whole plant being white or off-color. The whole plant can be easily pulled from the soil. The roots and crown will be a discolored brown rather than being a healthy white or cream color.

Heat sterility is a strong possibility this year. With sterility issues often just the tips of heads are white and shriveled.

Fusarium head blight (scab) causes wheat head tissue to turn a purplish white or the heads often have some green and some whitish spikelets. If the whole head is infected the stem right below the head looks brownish to purplish.

The barley yellow dwarf virus infections may cause whole plants and heads to turn prematurely.

Herbicides and hot temperatures generally add stress to wheat plants. This situation can cause premature white heads in which the majority of the plant stays green but heads are white. A common symptom is for this to occur in patches, sprinkled in an area or in strips.

Marcia McMullen, Extension Plant Pathologist at NDSU, believes it is possible for a number of factors working together to cause white heads.

Tree of the Week

The Ohio Buckeye is a rare tree of this area but there are a few. Like many other trees, it is not very drought resistant. It also tends to do better in areas where the soil pH is between five and seven. Most of our soil sites are above 7 so it does have some toleration of slightly basic soils.

Ohio Buckeye is a medium-sized tree with an oval to rounded crown. The unique characteristics about this tree include the palmate compound leaves, terminal candle-like flowers and large globose fruits. The leaflets are about 3-5 inches long and arranged much like spokes on a wheel. The margins of the leaflets are finely serrated with pointed tips.

Look for this tree to grow 20-40 feet high with almost an equally spread of its crown. So, it has a lot of potential for shade. It forms a tap root which makes the root system much different than most other trees grown in this region.

Ohio Buckeye has no major insect problems. In fact extracts of this tree species are topic to some pests.

Some of the suggested cultivated varieties include Autumn Splendor, Homestead and Prairie Torch. These have been released by the University of Minnesota, South Dakota State University, and North Dakota State University.

If you give this tree the opportunity to grow with supplemental water, look for a medium green leaf color during the growing season and a yellow to amber fall color. Without sufficient water, the leaves will easily scorch.