Pasture with lots of weeds

Asked June 6, 2014, 4:48 PM EDT

Greetings, Our pasture is at 7000' in N Larimer county. This year the cheat grass (downy brome) went nuts. It's knee high and has taken over several acres of pasture which is supposed to be native grasses. We also have quite a bit of mustard and penny cress. Normally we'd think about haying with grass as thick as it is this year. My questions are:
1. If we hay while the cheat is green, will it be OK for the horses to eat when it's cured? What about goats and cows?
2. If we DON'T hay, but cut and just leave the cheat on the ground, will the green seeds mature after they are down and then be a problem for next year. (I.e. we'd have to spray this fall or spring.) Your advice would be very helpful.

Larimer County Colorado pastures and forages

1 Response

Hello There,

I would not feed cheatgrass to any livestock in hay when harvested at this time of year. Even though the cheatgrass my still have some green, most of the plants have produced seed with awns. The awns and calluses of the seed can cause problems in the mouth of any livestock that eat it. In the pasture, animals will avoid eating cheatgrass, but when it is in the hay, they don't have a choice. One option would be to mow the cheatgrass areas right now with a mulching type mower so that you can wait a couple of weeks to hay and not worry about it being in your hay.

Yes, if the seeds are mostly filled (even while green) they may be near maturity and a proportion of the seeds will be viable and be a problem this fall and next spring. Most of the cheatgrass will begin growth in fall/winter each year and then will continue growth the next year before reaching maturity (winter annual) around May 1 to May 15, depending on elevation. Treating cheatgrass could start in the fall or in Feb/March by recognizing the small seedlings coming up and spraying them with glyphosate (Roundup) while the other grasses aren't growing yet. Spraying with Plateau (panoramic) is another option. Here is a fact sheet with a little more information on cheatgrass control - http://www.ext.colostate.edu/pubs/natres/06310.html

If you have other questions, please let me know. Feel free to email me directly.

Sincerely,