by Jerry Volesky, Range Scientist
The 2019 growing season continues to be quite favorable. Cooler April and May temperatures did result is a delay of grass growth. At GSL, forage year (since last October) precipitation has been above the long term average and fairly similar to 2018 (Table 1, Figure 1). Although June precipitation at GSL was slightly below the average; total precipitation during the critical months of May, June, and July was above average.
Annual upland range production in the central Sandhills averages about 1,850 lb/acre. In 2018, production was 15% greater than average and that above average production will likely be the result for 2019. This is consistent with the Grassland Production Forecast (Grass-Cast), a model for the Central and Northern Great Plains, which include historical GSL production data (Figure 2).
By August, the vast majority of growth for both cool and warm-season grasses has already occurred. Additional rainfall in August will generally not promote additional growth, but rather, help maintain those plants in “green” mature state of the warm-season grasses. Late August and September rainfall will stimulate growth of cool-season grasses into the fall.
| Average | 2017-2018 | 2018-2019 | 2018-2019 Cumulative | |
|---|---|---|---|---|
| OCT to MAR | 3.36 | 5.52 | 6.04 | 6.04 |
| APR | 2.14 | 2.45 | 2.05 | 8.09 |
| MAY | 3.04 | 6.67 | 6.28 | 14.37 |
| JUN | 3.66 | 4.15 | 2.86 | 17.23 |
| JUL | 2.95 | 4.51 | 3.48 | 20.71 |
| AUG | 2.15 | 0.5 | ||
| SEPT | 1.76 | 2.24 |
Figure 1. GSL forage year precipitation through 7-31-19.
Figure 2. Grass-Cast grassland production forecast map released 7-16-19.