Cattle should be removed from wheat pastures when the crop reaches first hollow stem (FHS). Grazing past this stage can severely affect wheat yields. For a full explanation, please refer to the companion article in this eUpdate, “Optimal time to remove cattle from wheat pastures: First hollow stem.”
First hollow stem update
To screen for FHS during this important time in the growing season, the K-State Extension Wheat and Forage crew measures FHS on a weekly basis in 12 different commonly grown wheat varieties in Kansas. The varieties are in a September-sown replicated trial at the South Central Experiment Field near Hutchinson.
Ten main stems are split open per variety per replication (Figure 1), for a total of 40 stems monitored per variety. The average length of the hollow stem is reported for each variety in Table 1. As of February 23, no variety had reached first hollow stem; however, a few varieties had begun stem elongation (Figure 2).
Figure 1. Ten main wheat stems were split open per replication per variety to estimate first hollow stem for this report, for a total of 40 stems (10 per repetition) split per variety. Photo by Luiz Pradella, K-State PhD student.
Figure 2. First hollow stem (initial stem elongation) observed at 10x magnification. Photo by Luiz Pradella, K-State PhD student.
Table 1. Length of hollow stem measured on February 17 and 23, 2026, of 12 wheat varieties sown in late September 2025 at the South Central Experiment Field near Hutchinson. The critical FHS length is 1.5 cm (about a half-inch or the diameter of a dime).
|
|
First Hollow Stem (cm) |
|
|
Variety |
02/17/2026 |
2/23/2026 |
|
AP CP17CU3493#009 |
0 |
0.01 |
|
AP Sunbird |
0 |
0.02 |
|
AP24 AX |
0 |
0.01 |
|
CP7017AX |
0 |
0.03 |
|
CP7599CLP |
0 |
0.00 |
|
Gallagher |
0 |
0.03 |
|
KS Bill Snyder |
0 |
0.00 |
|
KS Providence |
0 |
0.00 |
|
KS20HD134 |
0 |
0.00 |
|
KS211130 |
0 |
0.00 |
|
PlainsGold Sheridan |
0 |
0.00 |
|
Zenda |
0 |
0.17 |
|
Mean |
0 |
0.02 |
* For reference: 1 inch = 2.54 cm, or 1 cm ≈ 0.3937 inches
We will report the progress of first hollow stem during the next few weeks until all varieties are past this stage. Additionally, first hollow stem is generally achieved within a few days from when the stem starts to elongate, depending on temperature and moisture conditions. Therefore, we advise producers to closely monitor their wheat pastures. Since each farm/crop reality is unique at the field level.
The intention of this report is to provide producers with an update on the progress of first hollow stem development in different wheat varieties. Producers should use this information as a guide, but it is extremely important to monitor FHS from an ungrazed portion of each wheat pasture to make the decision to remove cattle from wheat pastures.
Contact authors:
Romulo Lollato, Wheat and Forages Specialist
lollato@ksu.edu
Luiz Otavio Pradella, PhD Student – Wheat and Forages
pradella@ksu.edu
K-State Wheat and Forage Team:
Jazmin Gastaldi, Master Student – Wheat and Forages
Fabrizio Bianchi, Visiting Scholar
Bruna Ramos, Visiting Scholar
Amanda Scarabello, Visiting Scholar
Joao H. Veira de Almeida, Visiting scholar
Jorge Cuellar, Research Scholar