Andrew Roesner

here's some good info about the affects gypsum has on soils, if indeed you are using gypsum:

http://www.cmtmi.com/gypsum.asp

Thanks for the reply R Jay. I've done all the math and I understand how to calculate the circumference or a circle. I'm hoping someone might be able to give me an idea on what radius to use for the bender without having to resort to trial and error. The 41' i mentioned is the distance between the ends of the hoop after bending. That distance *should* be about 31' -32' for a 30' diameter greenhouse. In other words, hoops bent on bender built on a 15' radius produced a "diameter" of 41'.  

Hi All!

I am in the midst of building my own hoop house. it's 30' wide and 95' long. The many "build your own greenhouse" websites that sell hoop benders don't make a 30' bender so I'm making my own. The first version is a 4'x 8' sheet of plywood cut in half length wise and screwed together. I stretched some masonline out to a 15' radius and traced the arc on the plywood. I used the cut out from that to add a 3rd ply in the middle of the two sheets and set it back about a half inch so the there is a groove where the hoop can rest while bending.

I gave it a try on saturday and everything works fine, except the hoops do not form a 30' diameter. not even close. I'm using 2 24' lengths of 1 5/8" top rail to create the hoop. the obvious answer is that the hoops snap back a bit after bending and so I'm guessing the radius of the bender needs to be less than 15'. the question is, HOW MUCH LESS!?! the approximate diameter when the hoops are assembled on the ground was 41'. I know that the diameter when assembled should be a foot or two wider so that the hoops will have some tension when setting them, but this is too much.

does anyone have a suggestion of what radius to try to achieve my desired 30' diameter. is there maybe an equation? i've looked quite a bit but i've not found anything on the interwebs. does anyone have a link to point me in the right direction??

I found a website that mentions a 10% spring back which means i might want a 13.5' radius. I'd hate to cut a new radius and end up with it too narrow!

Thanks for the help!

Travis Johnson wrote:In life there are things we want to do, and then there are a few surprises. As farmers we just have to roll with it. In this case, I would just sow down winter rye exclusively and you will be well ahead in the Spring time. Is it the ideal mixture you wanted? No, but it was not your fault, delays happen, so use what you can this year, and next year try your ideal cover crop mixture when you can get an earlierjump on it. Winter rye by itselfis an excellent cover crop and why so many farmers rely on it.

Hi Travis. Thanks for framing the problem in this way. We so often want to make everything just exactly perfect! The Winter Rye will certainly thrive if planted soon. I think I'll go ahead and plant some vetch with it as well. Our warm sunny days in autumn keep the soil reasonably warm well into November.

Todd Parr wrote:I use tillage radish a lot, but if it doesn't have at least 8 weeks or so before it frost-kills, it will have pretty limited growth.  If you have 8 weeks, I would try it.  Otherwise I would save the seed for later.  Nothing says you can't plant tillage radish in the spring as long as you don't need that area for planting then.

Hi Todd. Thanks for giving me that time frame. I don't think we have 8 weeks unfortunately. And that radish seed is a bit pricey! I like the idea of planting some in the spring. I use no more that 4 acres next spring so the rest will be in cover again for the summer.

Thanks Ryan, sounds like Daikon might still be on the list! I'm planting it for its ability to grow huge tap roots and break up the soil and then leave lots of organic matter behind so it wont be harvested (well, maybe a couple!), but if you think it will germinate and grow well until the soils freeze then I might try it!

Drew, looks like tick beans might be what we call fava beans up this way? Thanks for the recommendation! They might work great in this system!

Hey All,

FINALLY! I have ~16 acres of Northern Colorado farmland in my possession. The corn has been off the land for almost a month now but I didn't hear about it until last week. But that's a whole other story! I very much want to cover crop this fall, IF it's still possible. My plan is to plant Hairy Vetch at 30# per acre, Daikon Radish at 20# per acre, and Winter Rye at 80# per acre. The previous farmer is willing to prepare the soil and we've also found someone with a seed drill setup who will plant for us. We access to all the irrigation water we could ever need. The farm is zone 5B. My goals for cover cropping this fall are building soil organic matter, building soil nutrients, and suppressing weed growth. Any cover crop planted this fall will chopped and dropped on the spring and a spring cover crop planted. My questions for you:

Is it too late to plant that mix of crops? Is it too late to plant any mix of crops? Do you have any ideas for cover crops that I could plant now (in the next week) that would be more successful than those proposed above?

of the three the one i'm most iffy on is the daikon radish. I don't think the roots will get all that big in the remaining time we have and the seed is expensive.

Thanks for the help!

Daron Williams wrote:A note on wood chips and nitrogen. If you don't till in the wood chips and just leave them on the surface you should not see a decrease in N levels. My understanding is that the locking of soil N only happens when you bury the wood chips or till them in.

Thanks Daron. Any idea how wood chips on the surface can reduce soil pH? Perhaps over a very long time frame as they break down?

Bryant RedHawk wrote:hau Andrew,  Have you read my soil threads? They will probably give you some good ideas which will help you develop a good plan of attack.

Hops is a heavy feeding plant just in case you didn't know that.

The tool you might want to use is called a "Key Line Plow" To use one on large acreages you will need a large (150+ hp. tractor) to pull a 4 tine model.

Redhawk

KEY LINE PLOW!! Thank you Bryant! I had come across that name at some point but it had escaped me until you reminded me! Most of the farmers in my area have very large tractors. I wouldn't be surprised if a few have something that big. Having the key line plow, now that's another story!

I did know that hops are very heavy feeders. I've been immersing myself in the world of hops production for months now. The standard recommendation for N is 150-200 #/ac, all of which is applied in a short 6 week window from mid May to the end of June. They're quite remarkable plants. Now that recommendation comes from conventional farmers of course. Most hops are grown like anything else with little to no attention paid to soil fertility. I'm sure my young plants in poor soil will require more than 200# N/ac, but I hope and am planning, to build organic matter and fertility over the years so that number will be greatly reduced.

Chris Giannini wrote:If it were my land I wouldn't drill or plant anything until you fix the ph problem. I would start with doing a few lab tests on different areas of your farm. Once you submit samples and get results I would suspect that the soil in low in phosphorous for which I would apply a large amount of fish bonemeal to bring the ph down

Chris, the pH issue is a big one for us. You'll see in my original post that hops like a slightly acidic pH, and that high amount of free lime (6%) is making pH adjustment very challenging. I had planned to start a separate post regarding soil pH, but I'll give a quick overview of what I've learned and maybe you'll have an idea.

The folks at the Colorado State University Soil Lab did all my soil testing. I learned from them that an acre of soil that is 6" deep is considered to be 2,000,000 lbs of soil. So considering that my soil is 6% free lime (CaCO3, Calcium Carbonate), I have 120,000 lbs per acre (in the top 6" of soil), or 60 tons, of CaCO3 that is keeping my pH high. I also learned that every lb (or gram or ton, for that matter) of CaCO3 in the soil requires 3 lbs of elemental sulfur to neutralize it. So 60 tons of free lime per acre needs 180 tons of elemental sulfur to neutralize it. Not only is that amount of Sulfur unfeasible from a financial standpoint, it's affect on the soil would be disastrous.  I've been in contact with a company in California that sprays Sulfuric acid in these situations, but have yet to receive a cost quote. And then there's the damage of spraying sulfuric acid!! Interestingly, when sulfuric acid reacts with CaCO3, the products are H20, CO2, and a bunch of CaSO4 (gypsum)!

If you have a proven method for lowering pH quickly and efficiently, that takes into consideration the CaCO3 levels, I'd love to hear it!!