By Romulo Lollato, Wheat and Forages Specialist
Many varieties are now past first hollow stem (FHS) in the Hutchinson region. In some cases, a few selected stems in early varieties had already one visible joint as of March 8 (Fig. 1).
Figure 1. Some varieties already had the first joint visible by March 8. Photo by Romulo Lollato, K-State Research and Extension.
The average length of hollow stem for each variety, as well as the percentage of stems that reached FHS at time of measurements, is reported in Table 1. As of March 8, the varieties 1863, Gallagher, WB4303, WB-Cedar, and WB-Redhawk were past FHS in our test plots near Hutchinson. Varieties approaching FHS were Everest, KanMark, LCS Pistol, LCS Wizard, Overley, Ruby Lee, SY Flint, SY Wolf, TAM 114, WB4458, and WB-Grainfield. Varieties were considered to be approaching FHS when either selected stems were past FHS or when average hollow stem length was approaching 1.5 cm.
At this time, dual-purpose wheat producers who intend to harvest the wheat crop for grain should either have already removed cattle from their wheat crop or be preparing to do so for the varieties mentioned above. Grazing past FHS can severely impair wheat grain yield. Previous research in north-central Oklahoma has shown that grazing past FHS can lead to yield losses ranging from 1-5 bushels per acre per day, depending on weather conditions at grazing termination. Hot, dry weather increases yield losses associated with grazing past FHS. Varieties that have not yet reached FHS at time of this report may allow for a few additional grazing days, but producers are encouraged to actively scout their fields for FHS and already prepare to remove cattle at this time.
For more details on how to scout for FHS, please refer to Agronomy eUpdate article “Optimal time to remove cattle from wheat pastures: First hollow stem” in the Feb. 5, 2016 issue).
Table 1. Length of hollow stem measured on March 8, 2016 of 23 wheat varieties sown Sept. 26, 2015 near Hutchinson. The critical FHS length for purposes of cattle removal is 1.5 cm. Varieties highlighted in red are past FHS. Varieties highlighted in bold are approaching FHS.
Variety | Hollow stem length | Stems at FHS |
| | cm | % |
1863 | 1.54 | 60 |
Bentley | 0.69 | 0 |
Danby | 0.60 | 0 |
Doublestop CL Plus | 0.62 | 0 |
Duster | 0.74 | 0 |
Everest | 1.24 | 0 |
Gallagher | 1.51 | 50 |
KanMark | 1.18 | 20 |
LCS Chrome | 0.73 | 0 |
LCS Mint | 0.70 | 0 |
LCS Pistol | 1.22 | 10 |
LCS Wizard | 0.99 | 10 |
Overley | 1.35 | 40 |
Ruby Lee | 1.38 | 50 |
SY Flint | 1.07 | 10 |
SY Wolf | 0.91 | 10 |
T158 | 0.70 | 0 |
TAM 114 | 1.04 | 0 |
WB4303 | 2.26 | 100 |
WB4458 | 1.38 | 40 |
WB-Cedar | 2.26 | 80 |
WB-Grainfield | 1.15 | 0 |
WB-Redhawk | 1.74 | 60 |
Variety | P < 0.01 | |
LSD (0.05) | 0.52 | |
The intention of this report to is provide producers a weekly update on first hollow stem of different wheat varieties in the current growing season. Producers should use this information as a guide, but it is extremely important to monitor FHS from an ungrazed portion of each individual wheat pasture to take the decision of removing cattle from wheat pastures.