You don’t say what “kind” of hay has been growing there and for how long. And what other “stuff” has worked its way into the stand. Was it a “pure stand” to begin with?
Everybody always seem to say “contact your local extension agent” and I pretty much say the same. Why bother because IME most have a “generic” understanding of things and pretty much “recite from the book”.
But in all fairness some areas of the country may have better “extension agents” then others. But IME most have never grown let alone baled a single bale.
I have a small dedicated hay field 50+ acres of Orchard and 1/3 Timothy. With a yield of around 175-200+ tons a year. It was seeded in “bare” ground 12+ years ago. After having been used for “crops” corn, soy beans, etc for many years by the previous owner.
The process is not rocket science and pretty straight forward.
If you have far more “junk” grasses, weeds, etc. than grass hay most likely you will want to disk everything under, float and start back with a nicely prepared seed bed. This is a judgement call based on experience/understanding of “hay”. If in doubt as others have said look around for someone who has a nice hay field and ask for some advise. Drop a note in their mailbox and offer to pay a few dollars for their time. Most likely they will be happy to offer some up for free.
“Renovating”, adding to an existing stand or starting over from scratch the process is the same. You will need to pull soil samples from various parts of the acreage. It is generally best “divide” up the given acreage pull samples and label the bags where it was taken from. Because some areas may need more of “something” than others. But with only 15 acres I don’t think this warrants the time and energy. I would just pull say 10-20 plus samples from various part of the field toss the core samples in a plastic bag thoroughly mix together and fill say 5 sample bags to the designated line and send off to be analyzed. I made friend with my farmer neighbors and borrow theirs.
You need to “pull” the samples from at least 6" down. This can be done with a shovel, but is time consuming and a PITA. You are in an Ag state so I would like to think there are plenty of Ag/fertilizer companies that cater to farmers that will be amending you field. They should offer soil analyzing and lend the “tool” to pull soil core samples. It’s just a “pipe” with a foot “hold” that you push into the ground and then push out the dirt into a your bag. Makes for short work.
When you send the bags out to be analyzed be sure to label what is growing there and or what you will be planting. The report get back will be based on this.
The “report” is very easy to read. It will tell you exactly what you need and how much will be needed of each in lbs per acre.
Sounds like you have already contacted the company that will taking care of things. They will pull samples send out and tell you how much money you need to spend. The above is for those who don’t have this service. Or are in an area that doesn’t attract a lot interest in preforming this generally free service for just 15 acres. You don’t have to ask for specific test. They just need to know what you will be growing.
In my neck of the woods growing Orchard/Timothy the 2 main amendments are Potash and lime. With stands that are baled on a regular bases. Potash more than lime. Potash can and does cost $$$. Nitrogen can and does come into play depending on things. But not as much with a stand that is not baled on a regular bases. If the field has just been mowed more than baled most likely the nitrogen levels will be good hopeful potash also. Lime depending on things like geographic area, what the top soil is laying on, weather, etc.
If the field call for a lot of lime its best to spread it out over 2 seasons or so. Other wise a lot of what is spread will be washed away into the low laying areas or your neighbors field. Depending on the lay of the land. Lime takes around 6+ months to get into the soil as it is. Best to do in late fall depending on the geographic/climate. What ever the norm is for you location.
If you are going to “start over” kill off, disc everything under. I should think you would want to fertilize first as the soil report suggests. Then reseed next spring, late winter. What ever is the norm for Iowa. Around here late summer is the norm. But I did my fields in late March and my stand came in great. But my sold did not need to be heavily amended. If your does then you may want to wait until late winter. You local hay farmer would know best.
If what you have growing is looking OK but on the “thin” side of things it will be cheaper just to hire someone to “drill” more seed of choice to the existing stand. Around here Brome is added to Orchard/Timothy. Orchard/Timothy is a clump grass, meaning is grows from “clumps” and doesn’t “spread” like “lawn” grass. Brome is a good horse grass hay that does spread and fill in the spaces in between the clump grasses leaving little to no room for weed seeds to move in and become a PITA.
There you have have it. My understanding of things in my neck of the woods.
