My mulch mistake (growing grass)

I laid out a sheet mulch bed a few weeks ago, and on top of a 8"-12" layer of straw I have a 2" layer of composted manure, with another 2" of straw on top of that. I am stupid and for some reason thought that as the manure was advertised as "composted", that any seeds would be inactive. Anyway, I have grass growing out of that manure layer. Not good since some of our transplants are about ready to go. I was thinking of just completely removing the top layer of manure and straw. I was also thinking about just adding on another 8 inches of straw. Or dense compressed sheets of straw straight off the bale. I'm not sure if that would kill the grass fast enough though.

What should I do?

Thanks in advance for the advice.

are you sure the straw isn't growing the grass? straw is expensive as it's de0seeded hay of one type or another. I got doc out of the "composted manure" and grass out of the hay I composted it with. Everything i planted in the greenhouse turned into a plug of grass this winter. What happened to the cardboard layer the manure was suppose to go under and the straw was suppose to go over so one can't reach the light and the other can't reach the soil?

Doesn't really matter the pickle your in is grass is growing out of everywhere and more of a suspect component won't stop grass anyways. At this point all you could really do is peel off the mulch and give the situation a pitch fork flipping and hopefully the roots will get air pruned/ sun scorched before getting buried again. Did you remove the light exclusion barrier layer due to the miasma going around about toxicity in cardboard and newsprint? If you work at an office maybe you could raid recycling for less ink inundated paper or black plastic to solarize the grass but your short on time and allot of these solutions are weather permitting. With that much straw torching the grass is way out of line as much as plucking it out is not likely to work. The only hay mulch that hasn't grown grass for me when i was short on a light barrier was properly bogged out water logged rotten hay with worms in it everything else just starts more hay. The problem is if the seed is really coming from the straw it's not going to stop coming anytime soon, if it's coming from the manure you can toss the situation around at great labor and let the heavier manure fall deeper. The only real way though that wont break your back or use up allot of time is to peel off and light barrier the situation down, wetting the light barrier layer real good so you have something that's easy to punch through in a weeks time.

Best of luck, all our broad scale mistakes are permanently store on the internet for future generations to come.

Personally I just look at it as more green matter for my bed. I just chop it and drop it right where it falls. I actually encourage my rye grass to grow so I can chop it, close to the ground, and use the green grass as a mulch around my plants. The roots are providing benefits beneath the soil and the green tops benefits above the soil.

If you don't have a problem with newspaper add a layer of that and then the straw. You shouldn't need as
much straw that way.

Otherwise, get out the hoe. They still work.

The solution depends on how big an area you have there, how much time you have, what type of grass is sprouting and what you intend to plant there.

As the previous post suggest covering with card board or paper then a layer of straw will do the trick. If the grass is not a nasty species let it go and just make sure you don't allow it go to seed. Don't panic it will all work out there is plenty of nutrient there for you plants and the grass and next season it will be even better.
Cheers
Tim

chances are this "grass" is from the straw and its wheat or barley or oats. i leave mine to grow and harvest some grain off of it.

Thank you all for the helpful replies. On further investigation I can see that it is actually the straw (I only noticed this issue last night in the dark). To add, I have a manure layer under the cardboard that is on the bottom, but also towards the top underneath 2in of straw because I intended on seeding straight into it. I think I will take all of your advice and just let it go and chop it down. This is a suburban garden, less than 100 sq. ft., and I still have about a week until last frost, and so 2 or 3 weeks after that is when I plan to seed corn, then beans and squash. I can let it go for that long and then chop it. My dad already has transplants going too for vegetables. The plan was to drop cardboard and straw onto another area to start a bed for the vegetables.

With a new bed, I figure that I will leave out the manure layer at the top. When transplanting the vegetables, spreading the straw and filling in soil twice the size of the transplanted root system, and then mulching up to the plant once it is mature enough. Is there anything I should be cautious of since I know my straw has plenty of seed?

chop them sooner than later. before the true leaves develop. Anytime you lay down new substrate, or turn existing stuff, you run the good chance that some of the millions of dormant seeds will germinate. Leave the substrate undisturbed, and remove the offending growth via scissors, a sharp hoe or weedburner. Maybe not the last one with all that straw. After like 2 weeks, you will have a sterile seed bed ready for your plants.

okay okay... this might not be a popular choice, but after reading something from Paul Wheaton about if anything grows up... "just throw more straw on"... so I went a head and just threw on books of straw. If that does nothing, I will remove the books and chop it all down. This is, unless I get a unanimous "WHAT ARE YOU DOING?!?!?!".

Bobby, that's pretty much what I'do Plants need nutrients and light. Deprive 'em and the won't survive.
If seeds germinate in the straw, I just fluff the top layer, trying to avoid exposing more seed.
I'd put all my straw mulch on top of all my compost/scraps/manure etc for some serious stifling action!

I'm with Rich. Try not to disturb the soil if that is at ask possible.When you turn the soil you do to things that mean work. 1. Weed seeds are disturbed and may germinate.
2. You upset the soil organisms.

Feed your soil from above and let the bugs in the soil assimilate all that goodness for you.

Would you guys transplant into this bed or just straight seed into it?

Leila, I have another 4 bales that I need to use for some other stuff, but I might just put another bale on this bed and if I really really need elsewhere I'll just move some of the straw over.

Tim, I'll be sure not to disturb the soil, such as raking off the top layer.

Since my dad actually owns this house and the garden, and I'm trying my best to introduce no-till and all organic gardening to our home, and since I heard him mention Round-Up when I told him about the germination out there, I'm trying to find the quickest/best solution to this so he doesn't resort to spraying that crap. Wish me luck!