Karen, I'm trying to think of which tomato pathogens might be found in moldy straw. I don't think it would be any of the systemic ones, but I do think there's a possibility that there could be some of the foliage pathogens b/c they can stay in the environment for a long time.

And since the center of the bales is the most moist, perhaps some might have sporulated, thinking mainly of the fungal ones. But even if there are unsporulated spores still there it wouldn't be good.

If it were me I wouldn't take a chance, especially since you said it's no problem to get fresh bales.

I'd compost the bales you now have and then you have less to worry about.

Carolyn

I have done it - with hay, not straw - with no problems. This assuming you trim off the lower plant branches so there is no ground contact and avoid overhead watering/splashing. The old tends to mat badly for awhile and you do get some water repelling effect from that but it doesn't last long.

However, when fresh is readily available and the old won't go to waste either, I go for the fresh.

Another alternative is to use the old stuff around the outside edges of the garden to keep down more weeds. It also gives my armadillos something to play in instead of the garden itself. ;) It decomposes out there and then can be tilled into the garden soil in the fall - kind of "sheet composting".

Dave

I've been using spoiled (moldy) hay as a heavy mulch for over 20 years without issue. Just make sure you wear a mask when spreading the moldy hay/straw - your lungs will thank you!

TomNJ

I always think of Ruth Stout (the hay queen) when someone mentions spoiled hay.

I always thought the bacteria and fungi in spoiled hay were different species than the bacteria and fungi that cause tomato diseases but I don't recall ever really reading about this specifically so I really don't know.

I do know breathing the bacterial and fungal mold found in spoiled hay is not good for you. But this mainly would apply to a farmer whose exposure is chronic , particularly in enclosed space like a barn. I do try to remember to use a dust mask if I think about it when using moldy straw/hay which is something I do pretty regularly but respiratory problems would be VERY RARE even with frequent exposure.

But those mold spores just fly off the bale when it is split open- I still don't like to breath it all in if I can help it. But I never pass up an opportunity to get spoiled hay/straw cheap--great for adding organic matter.

Farmer's lung and TODS
http://www.cdc.gov/nasd/docs/d001501-d001600/d001504/d001504.html

Here is a link that might be useful: Hay gardening

I agree inhaling the hay mold is usually thought of as more of a chronic exposure issue for farmers, but before using a dust mask my lungs would often pain for two or three days after spreading a few bales. With the dust mask - no problems, so I don't take any chances anymore. The masks are cheap at Home Depot and comfortable to wear.

TomNJ

I always thought the bacteria and fungi in spoiled hay were different species than the bacteria and fungi that cause tomato diseases but I don't recall ever really reading about this specifically so I really don't know.

****

No doubt probably true Farkee, but I couldn't exclude the possibility that some of the foliage pathogen spores and bacteria had landed in a hayfield, and knowing the longevity of the fungal spores of foliage pathogens and bacterial foliage pathogens, I couldn't simply dismiss it as not being aa possibility.

It's nothing that I read anywhere, just my hypothesizing.

And being a retired Microbioogist ( infectious diseases, immunology, etc.) I'm always a bit leery about using moldy products whatever they might be.

I used hay as a mulch in my perennial beds for a couple of years long ago b'c I got it free, but stopped using it for two words: WEED SEEDS. LOL

Carolyn

I've been adding LOTS of spoiled hay and straw for almost 10 years as a permanent mulch on my garden. (40 bales per year.) If there's any problem with mold hurting my plants I sure haven't noticed it. My soil, plants, and yields just keep getting better, and my weeding and watering is kept to a minimum. It's way cheaper than buying clean, new straw or hay as well.

According to CDC article there could be a problem for a small percentage of farmers who work with spoiled hay or grain in an ENCLOSED area. But they emphasize an enclosed structure.

Gardeners working OUTSIDE with a limited amount of bales just a few times a year doesn't compare to the farmers exposure. Still good idea to wear a dust mask as an added precaution.

I collect straw bales used for holiday decoration in the fall once they are discarded. Great for the garden. Also good for 'lasagna' layering to create a bed.

Many people also grow in straw bales and it is recommended to let the bales weather for quite some time prior to planting. They are already decomposing and definately 'spoiled' before planting.

Thanks for everyones valuable opinions. I think, just to be on the safe side, I will get new, clean straw to mulch around my tomatoes. I may compost the moldy straw or as digdirt suggested use it at the edge of my garden where it won't be in contact with anything to suppress weeds there. I do try to be careful not to get any off it in my lungs. My brother is a farmer so getting fresh straw isn't a problem - just need to borrow his truck to haul it over to my house and this time of year (planting season and all!) they are usually busy using it but I'm sure I can wrangle a time. LOL!
I really need to keep my tomatoes producing this year as I am out of just about anything that I had canned with tomatoes in it - salsa, ripe tomatoe relish, chili sauce, BBQ sauce and just good ol' canned tomatoes. The family used a lot more salsa this past year then I anticipated and now I need to double the amount this season. That's teenagers for ya!
Thanks again!
Karen

I've used moldy hay for mulch many times. Any bales that are bad enough we can't feed them to the horses or cattle I use for mulch. Several of the hay men just give me their old bales when they go bad in the stacks. I have never had any trouble with any vegetable. I leave a couple inches of bare space around the stem. Here we are dry enough once you bust the bale open and spread it out the mold will dry out. If I didn't use the moldy bales I would find it hard to justify paying 5 dollar a bale for good hay to use for mulch. I also use grass clippings. JD