Local millers, grain brokers, agronomists and Penn State Extension educators from wheat-growing regions combed fields in mid-June to estimate yield and evaluate growth stage, stand density and disease presence in soft red winter wheat.
The annual tour looked a little different than usual this year but continues to be an opportunity for mills and brokers to help forecast what the wheat harvest has in store and anticipate how grain markets may be influenced.
More than 20 fields were evaluated across eight counties, seven of which are in the top 10 wheat-producing counties in the state. The fields had a wide range of winter wheat varieties, crop rotations, fertility management and pest management.
Look at management
The fields Penn State Extension was able to collect background data on had wheat typically planted after soybeans, but sometimes after corn grain. Planting dates ranged from Sept. 27 to Oct. 11.
A wide range of tillage practices were used, with no-till being most common, followed in prevalence by minimum tillage, including vertical tillage, and full tillage.
Almost all nitrogen was split-applied with a wide range of rates depending on preceding crop nitrogen credit, nitrogen source, tillage practice and predicted grain yield. Chicken litter was one of the nitrogen sources on two of the toured fields.
Use of growth regulators was variable but was more commonly used than not. No regional use trends were noted this year.
Almost all fields received both early and late fungicide applications. Widespread use of Miravis Ace, a new tool in the toolbox as of last year, was documented.
Pests and diseases
In most years, the main disease of interest is fusarium head blight, also known as head scab, since the fungus produces the mycotoxin deoxynivalenol (DON), also known as vomitoxin or “vom.” Head scab reduces grain yield and test weight, but its negative effect on grain quality is of great interest to millers.
A dry period around the time some fields were flowering, along with late-season fungicide applications, resulted in little to no head scab presence in many fields. However, with Pennsylvania’s cool spring, wheat maturity appeared slower and more variable in 2020 than typical. This made timing late-season fungicide applications difficult and may explain the low to moderate levels of head scab in some fields despite late fungicide applications.
Overall though, head scab levels were typically less than 1% in most fields this year with a few fields spiking at 5% to 10% incidence. Incidence of powdery mildew, leaf rust, Septoria leaf blotch and glue blotch were found at low to moderate levels in a handful of fields.
Louisiana State University Ag Center , Louisiana State University AgCenter, Bugwood.orgRUSTY WHEAT: While fusarium head blight is the biggest concern for wheat growth, leaf rust is also something that can affect yields, though leaf rust was only seen sporadically in fields and at low levels.
Take-all was also noted in one field in the eastern part of the state, which resulted in a massive stand and yield reduction.
Very little slug or cereal leaf beetle feeding damage was seen and was at low levels when present, compared to elevated levels in 2019.
Remnants of freeze damage
One unusual note from the tour this year is the fairly widespread but variable amount of freeze damage.
Nighttime lows reached below freezing in isolated parts of the state in the second week of May. Wheat growth stage at the time of the freeze and field topography dictated the extent to what fields suffered or were spared from damage. Damage tended to be worse in lower-lying fields or areas of a field.
Lodging was also seen in some fields, though it was not widespread. No growth regulator was used in the field with the worst lodging; approximately one-third of the plants lodged and plant heights approaching 40 inches.
Lodging in other fields was noted where excessive nitrogen rates were used, such as where overlap occurred at field corners.
Overall, stands ranged from “fair” to “excellent” (25 to 40 plants per foot), with most above 35 plants per foot:
South-central region (Adams, Cumberland, York). In 2020, the five-field average yield was 110 bushels per acre, with a range of 81-139 bushels per acre. In 2019, the average yield was 81 bushels per acre, with a range of 60-120 bushels per acre.
Eastern region (Columbia, Lehigh, Northampton). In 2020, the seven-field average yield was 86 bushels per acre, with a range of 67-115 bushels per acre. In 2019, the average yield was 89 bushels per acre, with a range of 68-103 bushels per acre.
Southeast region (Berks, Lebanon). In 2020, the nine-field average yield was 99 bushels per acre, with a range of 44-119 bushels per acre. With the low “take-all” outlier (44 bushels per acre) removed, the average yield increased to 105 bushels per acre. In 2019, the average yield was 99 bushels per acre, with a range of 88-106 bushels per acre.
Mary Burrows, Montana State University, Bugwood.orgSCAB EVIDENCE: Several fields showed symptoms of fusarium head blight — premature bleaching of several spikelets and a distinct pinkish orange fungal growth.
At the time of the tour, most wheat was between the milk and soft-dough stages. Average yields presented were estimated several weeks before harvest and randomly sampled from a few locations in large fields. These estimates may not reflect actual harvest yields in different fields, even in the same area.
Since the wheat tour, more isolated heavy rainfall and wind has already caused lodging in some fields, which will result in lower yields.Source: Penn State Cooperative Extension, which is solely responsible for the information provided and is wholly owned by the source. Informa Business Media and all its subsidiaries are not responsible for any of the content contained in this information asset.