This morning was the first day this fall that I scraped car windows. We are, for the most part, enjoying an unusually long fall with a few sporadic shots of welcome precipitation. The winter wheat looks good. Good growing conditions have given it time to produce tillers with the rains helping.
Some fields of winter wheat appear to have some volunteer spring wheat growing in them. This could be the result of winter wheat seeded into spring wheat stubble or it could be the result of some spring wheat contamination in fertilizer or the winter wheat seed itself. Much of this spring wheat is noticeable this year because it is already elongating and producing joints. The spring wheat will die with 20 degree or lower air temperatures and should not cause any major problems unless the proportion of spring wheat is very high.
There are some varieties of winter wheat that have a more upright growth habit. However these should not begin to joint this fall.
The extended warm weather has brought some concerns that aphids and wheat curl mites could become a problem. To date and to my knowledge, neither of these insects have been reported. However as wheat curl mites are difficult to see by the naked eye due to their small size, there could well be pockets of them.
There have been reports of leaf rust on winter wheat in NE. I received one report from SD. This is another pest that will not overwinter here. SDSU Plant Pathologists are not recommending any treatment for this reason.
All winter wheat fields should be scouted thoroughly this fall for weeds. This is an ideal time to control many weeds that can cause problems in winter wheat.
A seasoned eye may note that the occasional field of winter wheat is showing some mild nutrient deficiencies. This seems to be more common in fields that were fallowed this past summer due to a failed winter wheat crop or some other reason. Many of these fields were planted relatively early and have lots of growth and tillers. This deficiency could be attributed to “fallow syndrome”. In other words, when fields are fallowed, they do not have living roots that can support and enhance growth of soil microorganisms and fungi. Many of these fungi play an essential role helping plants to access nutrients like phosphorus and potassium, which are not mobile in the soil. The fungi send out hyphae which attach to roots and act to extend the area in the soil that the root can explore and draw nutrients from. In time and with the presence of live roots, soil microorganism numbers should increase. Addition of a starter fertilizer at seeding can help avoid this problem. The addition of fertilizer to these fields in the spring will alleviate this issue. Adding fertilizer this fall is not recommended.
Thanks to Bob Fanning, Claire Stymiest, Emmanuel Byamukama, Dwayne Beck, Adam Varenhorst and Reid Christopherson for help with the above observations.
SDSU Agronomy Field Specialist
412 Missouri Ave.