Each treatment (cover crop or bare ground) must be 2 combine header widths OR at least 30’ wide by 300’ long. Each site has 2 reps of each treatment cover crop and bare. That makes the minimum experiment dimensions 120’ wide by 300’ long. Overview of the field layout. Most growers chose to leave a bare strip the length of the field (instead of the 300’ minimum length).

Very little or not at all. Other than leaving a bare strip, growers are asked to do everything else they would normally do on that field.

Any winter cover crop species or any cover crop species mix. They will need to overwinter so there is surface residue when the cash crop is planted.

You can enroll a site/grower on the “Tech Dashboard” at onfarmtech.org. View the instructions on how to enroll here.

No. Codes are generated new each year.

No.

No surface residue. It might mean spraying for early spring weeds. Some winter weeds or small weed patchiness is ok but we need to see bare ground soil. It must be easily distinguished from the cover crop.

In a KoBo form called ‘psa_farm_history_survey’. You will need to log on to a KoBo account using a state username and password supplied to you. See a video about filling out the form here.

Sure, maybe – but as a reminder, the systems we are studying are reduced-till. The cover crop cannot be tilled in, it must remain on the surface. Organic growers that use cover crop residue as their weed management program will find the bare ground area challenging. Cultivation passes will disturb our decomposition and soil moisture studies.

Yes. Typically, we recommend adding about 30 to 40% more growers than you think you will need in the coming year. For a state that deploys PSA research at 3 sites, we recommend recruiting 1 to 2 extra locations. (Remember, single growers can have multiple locations.) This is in the case of site failure. Failures can include: failure to plant or establish cover crops; lack of bare ground; poor crop establishment; floods; wild hogs, etc. Do you need to add your extra grower to Site Enrollment? Yes, go ahead. They can always be deleted later.

No/ Depends. The systems we are studying are reduced-till. We are studying in-tact surface residue from the cover crop. This means that the cover crop is not plowed under, and the ground is not disturbed prior to crop planting or during the crop growing season. There are some exceptions, like strip till, where just the inches around the planting bed is disturbed for seed soil contact, but the between row area remains in-tact. Or subsoiling with a shank that doesn’t disturb the surface.

Here is an overview and timeline of activities during the season. Growers are asked to be surveyed about their farm management practices (~ 30 min). Researchers will be in the field an average of eight times: biomass harvest, five decomp bag collections, sensor installation, and harvest. Growers can expect researchers to be on their farm at cover crop termination taking samples. They will leave mesh bags in the field throughout the season that can be sprayed over. Sensors will be installed after crop planting and can also be sprayed over. Just avoid driving in the row where they are installed. Growers will also be asked to share their yield monitoring data for the land just where the strip trial is located.

Not currently. Our data ingestion is not designed to handle alternate experimental designs to the original one site with 2 reps. For powerful statistical models, we would rather have more sites than more reps on one site. If you are interested in adding more sites or reps, contact saseehav@ncsu.edu for more information on purchasing additional Acclima TDR sensors.

Any amount of time, from zero to 20+ years. We would like a range of field histories. We will collect that information in our psa_farm_history_survey KoBo form. The only requirement is that the grower has experience and proficiency with cover cropping.

For growers continuing with the trial for more than 1 year, field sites can change from year to year. Crop rotation is a regular management practice, and we go wherever the farmer wants us. If that means a new field or the same field that works for us.

Yes. Any fertilizer is allowed.

Any time.

What is regionally appropriate. We want a wide range across the US. From 1,000 to 10,000+ lbs of dry matter from the cover crop. We understand that even 500 lbs is sometimes appropriate in colder climates. This is fine! We just want the cover crop treatment to be distinguished from the bare ground area.

+/- 4 days before or after cover crop termination. This is on the farmer’s own timeline. You can collect it prior to that if you communicate with the grower. You don’t want to handle herbicides in ground biomass and can trust the grower to terminate immediately after you harvest. Collect it after if a grower calls and says, ‘hey, I just sprayed that field.’

Whatever way the grower wants, it just has to remain on the surface.

Any spacing. The decomp bags are about 10×24” wide, so they would fit nicely in a 30” row, but we can even work with 7.5” drilled beans and we can trim plants to make the bags fit.

After the crop has emerged. This is generally 1.5 to 2 weeks after planting, which, if growers terminate about 2 weeks prior to planting, can be up to 30 days after the time you took biomass data and are doing your T2 decomp bag collection.

Onfarmtech.org

crownproject.org/

Yes, for soil texture at 3 depths, one for each sensor depth. No, not for soil fertility at this time.

The average two-person team visits a site for 1 to 2 hours about 8 times. Example of a typical season:

• Fall site visit and establishment

• Winter check-in for cover establishment and bare ground check – confirm no volunteer cover crops or bad weeds. Possibly see grower in person to do a survey.

• Spring cover crop termination and biomass harvest

• T1 decomp bag collection, weed photos or ratings

• Sensor installation, T2 decomp bags, weed photos or ratings

• T3 and sensor solar panel check, weed photos or ratings

• T4 decomp bag collection and possible sensor firmware updates

• T5 Harvest and sensor removal

Note: Chatty growers were not factored into the time estimates.