irrigated pasture question

Asked April 27, 2016, 1:02 PM EDT

Hello, I have a piece of irrigated pasture I had laser-leveled and plowed in 2014. I planted it with an irrigated pasture seed mix in December, 2014, and we received absolutely no rain until May, 2015 when it rained almost daily all month. Prior to that in March and April, I saw no sign of anything growing, and thinking I had a total failure, I started irrigating it, mostly just to see how it would water, and hoping something good would happen. The weeds started growing profusely, mostly kochia and other broadleaves, but I was surprised to see just how much grass had sprouted below the weed canopy. I continued to water until I ran out of irrigation flood water in mid-July, when I mowed the weeds because I could no longer stand to look at them, and also because I did not dare to spray the young grass. The grass stand was surprisingly good near the top of the field, where the soil moisture was greatest, but patchy to poor elsewhere. I re-seeded the poor spots in the fall of 2015 with the same seed mix, and this winter we got a better cover of snow. In the spring of 2016, I noticed much better emergence of grasses, although I don't know if my re-seeding effort was effective or if I was seeing some latent success from the previous year. This year, I have a different weed problem. The plot is covered with a purple mustard weed quite thick in some areas although grasses may be growing below. There is also some undesirable annual grasses growing, but I'm not worried about that. My question is: would it be desirable to spray with some 2,4-D to rid the plot of the broadleaf weeds, and will the plot fill in eventually if I continue to irrigate it, and should I continue to try to seed in the bare spots? In addition to the irrigation I gave it in 2015, I have flooded it five times this year since March 22, and since it's a better water year this year than last, I expect to be able to irrigate it on a declining basis until after the end of July. Although the weeds were competing with the grass for moisture, I think they may have helped to provide shelter for the young grasses initially. I live in east Millard Co., Utah. Thanks, Tony

Millard County Utah

1 Response

Good luck with your pasture! I suggest you contact your local office for site-specific advice:

Deric Despain

County Director
Agriculture Faculty

Office: 435-864-1482