Testing straw for herbicide

I would like to use straw for mulch, but can't find organic straw. My work sells it, but I can't get any answers on what may have been used on the straw.  I took a chance and bought a bale.  
From everything I have read and seen everyone seems to grow beans to test the straw.  I got my bale to late for beans.  I'm in the process of building my greenhouse. I put the bale in the greenhouse to use as a shelf until I have a chance to build some.  I dug out a small hole, added some compost and planted to pea seed I presprouted in the house. I filled a jar with straw and water. This is what I water the pea with.
The positive is the seedling looks great. But I don't know how potent the herbicide is.  It's winter, so I have only watered 2 maybe 3 times.   I didn't use a lot of compost, but I wonder if the roots are still only in the compost.  So basically I'm not sure when I'm safe to say this straw is safe to use.
I'm hoping some of you smart permies people will be able to guide me.  In the meantime I will let that pea continue to grow.
Thanks

I unfortunately had the pleasure of dealing with this although it was hay not straw. Mine were on potatoes so a bit different but if I remember correct we saw it on the third set of leaves at my neighbors.   Interesting I never heard of this method of testing to soak the hay/ straw.

I hope it works out. It’s so sketchy buying anything for the garden these days.

Go to your local feed mill. Ask them who sells organic grain to them. Go to that farm and ask if they have straw.
In Ohio we have OEFFA, Ohio Ecological Food and Farm Assoc., www.oeffa.org. We can just contact them to see who has organic anything.
Maybe your states have something similar.

Peas and beans are both good indicator plants. My understanding of the herbicide seedling test is that you are looking for an ill looking seedling. The presence of herbicide will have curled or cupped sickly leaves, a more yellow/brown plant than green, overall not good seedling.  Tests generally are for two to three weeks.

Depending on how long you have gone, I think you might be safe!

What kind of straw is it? Wheat? Oats? Barley?

Around here, the biggest risk is wheat that has been chemically desiccated before harvest (using the molecule whose name shall not be spoken on this forum).

To my knowledge, oats and barley are less likely to be desiccated before harvest because it devalues the price. Bakeries and breweries won't buy it because the residue interferes with yeast/fermentation. Farms that sell to these markets are a good bet.

If I obtain fresh wheat straw, my practice is to soak it for a few  days to activate all the dormant microbes in the straw, further breaking down the desiccant molecule. I've never had problems (so far).

I was told it's wheat straw. I don't remember when I planted, but 2  or 3 weeks is about right.  The seedling in the straw looks way better than the ones in the garden.( Some critter is enjoying the microgreens I obviously grew just for it.)
Mainly I'm concerned there isn't enough contact with the straw for a conclusive test. If there was bad herbicide in the straw would it leech into the compost? Would using the straw water only a couple of times be enough to to deform the seedling?

I work at a co-op. I was telling a customer who was buying straw for her garden to be careful, that residual herbicide in the straw can kill veggies.  I was not saying the straw she was buying had bad chemicals, but to be safe she might test it. The man behind her was quite irritated with me saying the herbicide used in California dissipates in the sun and there is absolutely no danger.  He seemed to know what he was talking about, said it was part of his job. Made me look like the dumb conspiracy clerk. I would rather be cautious, and make sure it's safe.  Normally I don't use anything that isn't organic in my garden.  Just writing this makes me feel I've made a mistake. Maybe I wouldn't use it no matter what the results are???   I will have to think about it.
Thanks everyone for your wisdom.

Hi Jen, if your seedlings have roots growing in the straw and still look healthy after a few weeks the straw should be safe. Typical bioassay using beans takes avout 3 weeks from sprouting but those roots having been in contact with the potting medium the whole time. Once I wondered if I can use rooted tomato cuttings to get a faster result. It still took over 2 weeks for the new growth to show symptoms.

I am also wondering if the kind they use simply to desiccate the leaves will have a shorter half life compared to those for supressing broad leaf species throughout the whole season.

I used mine as a mulch and it leeched down ruining my crop. Thankfully I had no greens at the time to make compost. My neighbor did have greens so all his beds are ruined and must dig them all out because he made compost.

Hay and wheat are usually sprayed with different things that are both bad the hay is like public enemy number one bad. I had no idea my hay guy used that until this issue. I pretty much won’t use stuff off my farm anymore for the garden. Seeing a whole garden ruined has a way of making you think. Especially when you thought you were doing good :/

Joe Hallmark wrote:Hay and wheat are usually sprayed with different things that are both bad the hay is like public enemy number one bad. I had no idea my hay guy used that until this issue.

Joe, I know a good gardener who had the same problem with runoff from persistent herbicide applied under a power line. It contaminated his dugout and destroyed his gardens. It's a lousy situation.

I think it's important to differentiate between hay and straw. Hay is grass (or alfalfa) grown as animal fodder. Straw is the leftover stalks of grain crops.

To my knowledge, persistent herbicides are not used on grain crops. My experience is that any potential residue from short-term herbicides can be broken down in a reasonable timeframe if managed properly. Of course it's better to not have residue at all.

It does seem like persistent herbicides are widely used on hay crops in the U.S. Not so much in Canada, yet, but I'm watchful.

I'm so sorry Joe. It's what I worry about.  I'm not an expert, but I believe I read in a past post that mushrooms can help neutralize herbicide and other toxic stuff in your soil.  It's been a long time. I think I was posting about I used to use a systemic fertilizer on my roses, (before I knew better). I was asking how long it would be until the flowers would be safe to use.  I think it was Dr. Redhalk who told me about adding a mushroom slurry to the soil, to help detoxify the soil.  I wish I could help more, but I'm not very knowledgeable in this area.  It might be worth looking into.  Good luck to you.

Joe I'm on my phone and have a hard time remembering how to link a post.  So I will tell you if you look in gardening for beginners  How long does systemic stay in the soil? By Jennifer Fulkerson (me) it was a good amount of interesting information.  I hope it helps.