Wheat has a couple of issues this year
By D. Bruce Bosley
Last fall's weather was quite favorable for getting wheat established in Northeast Colorado. Some wheat planted in early to mid-September put on extensive growth before a very dry winter. A recent survey of wheat fields showed considerable variation in crop health due to differences in late fall and winter moisture reserves. Fields having good subsoil moisture had uniform stands, lush green leaf growth and healthy crowns and roots. On the other hand, fields having a combination of the excessive fall growth, lack of winter precipitation, and low subsoil moisture reserves, had poor to very poor crop health and field areas bare of living wheat.
Wheat in some of the healthier fields shows considerable yellowing on the tips of the leaves and whole tillers due to dieback from cold temperatures and moisture stress. Wheat has the capability to adjust the population of tillers in response to environmental conditions. Fields had very favorable conditions last September and early October so wheat tillering was exceptional. Dry weather since then is currently causing plants to cut back on the tillers in response to short moisture supplies. Harvest yields are the product of how wheat has compensated to the environmental conditions throughout its growth.
Brown wheat mites have also caused significant yellowing and dieback in especially dry fields. In some wheat fields, they have done significant economic injury. CSU has established several brown wheat mite trials throughout eastern Colorado this year. Through these studies, we hope to understand this wheat pest better in order to determine the conditions and mite populations that economically justify miticidal treatments.
Brown wheat mites are primarily a late winter and early spring pest that decline and disappear with advancing wheat growth and warmer spring temperatures. Mite scientists don't fully understand the reasons for this population drop. Current evidence is that this pest is beginning to decline in importance. However, continue scouting for mites and other wheat health and pest problems.
Russian wheat aphid infestations are beginning to show up in area wheat fields. Extension pest specialists recommend regular scouting for this and other pests to avoid letting pest problems reach levels that cause economic injuries. Contact me for information on scouting for this and other crop pests.
This is the time to apply weed control treatments to eliminate existing and developing broadleaf weeds and prevent others from developing prior to and following harvest. Avoid a repeat of last year's weed problems at harvest by applying season-long weed control herbicide now. Saving moisture is the gift you give to this year's crop and subsequent crops. Having weed free fields at harvest is certainly a bonus.
Many wheat producers routinely apply a mixture consisting of 2,4-D and one of the many long-term control herbicides even in fields that show no to few weeds. They have determined that these herbicide treatments are very cost-effective through controlling weed competition and reducing the need for weed control treatments during the post-harvest period.
Last year's tumbleweed crop, that has been rolling across fields all winter and spring, has dropped millions of seeds that will soon be germinating.
Please contact me about these or other cropping systems or natural resource topics at 970-522-3200 ext. 285 at Sterling or 970-542-3540 at Fort Morgan.