Seeding rate for pastures


Doug Bastian

Farm Seed Manager

Olds Seed Solutions, Madison, WI


For many years we have followed seeding rates for pastures that were geared more for hay production vs. grazing management. Three years ago Olds Seed Solutions had a visitor from Germany who was questioning our seeding rates. He was asking why we seeded at such a light rate. The Europeans were seeding at double or more the rates as Americans were. This prompted us to set up a pasture seeding rate trial at the Bill & Bob Guell Farm in Eden, WI in 1999. We had several goals for this plot. These goals included:

1) Normal seeding rate (25 lbs./acre) vs. High seeding rate (50 lbs./acre)

2) No fertilizer (particularly N) vs. applying N

3) Winterhardiness of Ryegrasses

4) Longevity of pasture mixes

This plot was seeded to bare ground in one-acre increments with no cover crop on April 28, 1999. We chose four pasture mixes: Multigrazer® 116, Multigrazer® 117, Multigrazer® 400 and Multigrazer® 800. All four mixtures contain legumes and several species of grasses. Due to the various seed sizes the seeding rates varied from 25-30 lbs./acre on the normal seeding rate and 50-60 lbs./acre on the high seeding rate. We had ample rainfall after seeding and had an excellent catch.

The plot was first tested on June 17, 1999 and first grazed on June 18, 1999. Before the 135 dairy cows were released on the plots, we scissors clipped each plot and sample was sent to Rock River Lab for analysis. Before and after grazing we used a plate to measure amount of grazed dry matter taken off the plots. The plots were grazed five times by the dairy cows and one time by the heifers in August for clean up.

We wanted to see what affect fertilizing vs. no fertilizer would do to dry matter yield. We fertilized twice the in 1999. The first time after the first grazing in June and then again after the last grazing in August. To our surprise we did see a response on the normal seeding rate, however did not see the response on the high seeding rates we were expecting. Our assumption for this lack of response was the high seeding rate had double the plants utilizing an equal amount of N that the normal seeding rate was using so would not respond in the same manner. In 2000, we adjusted the rate and did see the response we were looking for. See the Two-year summary on the following pages.

Observations after Two Seasons:

1)      Higher seeding rates do pay for themselves because we see much less annual weed competition. The 50-60 lb. rate per acre may be a little extreme, however 30-40 lbs. per acre may be more realistic and economical. In this plot we saw very little bare ground in the high seeding rates and we are evaluating changes in pasture species percentages. The legume components thrived and increased in the second year.

2)      Fertilizing with N seems to pay for itself when pushing a field for maximum production. In 2000, we had to shorten the rotation period in order to maintain maximum return. We observed a response to the N applied that varied from 446-2976 additional lbs. of dry matter with an average increase of 1667 lbs./acre.

3)      The winterhardiness is still being evaluated since we have had mild winters the past two years.

4)      Longevity of stand will continue to be observed. To date we have not added any additional seed to the plot.

5)      The Guell brothers have observed an increase in production with each time they grazed the plot. Due to the complexity of the trial we did not measure the amount of increase in production. They were feeding 65-70 percent dry matter from the plot and 30-35 percent from TMR mix.

6)      The Multigrazer® mixtures vary in legume components from 20-38%. As you can see on the two-year summary the plot has averaged between 22.86-24.12 crude protein and 150.28-150.66 relative feed value. We look forward to the next few years to see if this will continue.