I planted some Italian Ryegrass (3# acre) as a nurse crop with alfalfa last year. For the most part this rye isn't suppose to head out in the seeding year, or over winter, except in mild winters. (Guess what we had last winter?) It's back with a vengence this spring. Is it going to choke out the alfalfa? Anyone with experience with this? Conventional alfalfa, not Roundup. Any input would be appreciated.
Re: Italian Ryegrass
I Googled "Italian Ryegrass Control" and I began wondering who recommended seeding Italian Ryegrass with your Alfalfa. It seems it's become a very difficult to control "weed" in parts of the country, and is very resistant to glyphosate in most cases. They recommended using a heavy application of Clethodim (Select) with glyphosate added to it for post emerge control...but don't expect to completely control it with that plan. Fall application of Command or Dual are part of the system they've come up with to control it, but I'm not sure it's approved on alfalfa.
Re: Italian Ryegrass
We have a mixed bag of annual ryegrass varieietes (30 yr old reseeding stand) and other cool season grasses in pastures. These are naieve to glyphosate use so no resistance problems at this time. We use both OTT applications and grazing to control overly dense ryegrass in clover and conventional alfalfa (falcatta). They key is to control the reseeding rate and it is good you only planted 3 lb/ac.
For OTT ryegrass control we use clethodim (Select 2EC) at 6-8 oz with 1% synthetic crop oil (Synox brand from Estes/Winfield) at 15 GPA with 110 degree Airmix nozzles). I see no clover or alfalfa damage with this surfactant but have not tried other oils. Higher rates of clethodim or oil may damage the legume, read the label. Either spray in late winter/early winter (just before or at early joint preferably the first or second 50-60 F warming trend) or about 2 weeks after the first cutting. Be patient, it takes about 10-14 days for clethodim to work...grass will begin to yellow then go down. Before doing the whole field, try this from a pump sprayer on a small known area...good coverage is key.
The other management you can do is cut when ryegrass at the boot or early emergence stage. This is not complete control however as ryegrass can soon grow a new very low head from near the crown. FWIW...with grazing we need about 0.5-0.8 AU per ac at joint/boot for control of ryegrass overseeded into bermuda.
For clover and alfalfa establishment in fall, cereal rye (Elbon variety) is preferred. Control in spring is much easier either spray at early joint with clethodim or mow in the boot+ stage. Some insecticides can be mixed with clethodim, Proaxis for example. For spring alfalfa just plain Bob oat works well as a nurse crop, it heads in about 70 days after emergence here then can be mowed....broadleaf weeds are normally a bigger problem in spring vs fall establishment.
The burndown mix I'm playing with now is a mix of generic glyphosate and clethodim at 15 GPA. The per ac rates are: 1.75 lbs AMS, 0.5% synthetic crop oil, 2 qt generic glyphosate, and 6 oz clethodim. IF any bermuda is present it will be suppressed while the cool seasons are controlled....curly doc, milkweed, and sedges are the escapes. Here is a pic from 2 weeks post application, bean burndown on the right and aa new alfalfa test strip coming in from the left (sprayed and planted the same day). One of these links should work. I'm no herbicide expert by far, but this is what works here.
My situation again is grazing not hay cutting. So what I do may differ from what works best for you. At one time, I felt grass in clover was a sin but what I have observed is that leaving the grass in there and cortrol grazing height keeps broadleaf weeds suppressed. If I want more clover then the seeding rate is increased. The added cost is offset by not having to spray herbicide.