Land Swap

Horticulture production can be very intensive, with a lot of soil disturbance, exposed soil, and little crop inputs returned to the system. This can deplete soil carbon and decrease soil health. This can cause decreased crop yields over time and make the field less resilient to the impacts of climate change, such as longer periods of drought or intense rainfall.  

Pastures, on the other hand, tend to have high soil carbon and higher soil health compared to horticulture production. Pastures have continuous plants present, which adds carbon through living roots and decaying plant material. Soil is also permanently covered, preventing erosion. Livestock also increase soil carbon by cycling the plant material into manure, which is spread over the pasture and incorporated into the soil.  

Converting a horticulture field to a pasture can increase carbon sequestration through the mechanisms listed above and it also has the potential to decrease GHG emissions. Improving soil health and incorporating manure can lower fertilizer requirements for the following crop. It can also reduce disturbance from tillage and farm equipment traffic during the pasture phase.  

Hear from one of our land swap producers on why they wanted to participate in this activity:

The land swap BMP involves pairing horticulture farmers with livestock farmers to incorporate grazing into high disturbance rotations. This BMP is regionally unique as Nova Scotia has a very diverse agricultural landscape, unlike agricultural regions in some of the larger provinces. It is common to have horticulture and livestock production in the same region.  

Horticulture fields are seeded and fenced to form a pasture for three years. After that, the pasture will be terminated and the field will go back into a horticulture rotation. We worked with each of our producers, both livestock and horticulture, to decide which pasture seed mix would be best, which fencing systems would work for that field, and the best ways to ensure water for livestock.  

We are using cross fencing to implement rotational grazing. Rotational grazing can increase carbon sequestration by encouraging root growth, improve pasture composition though fully grazing all plant species, and ensure more even distribution of manure across the fields.  

In addition to increasing carbon sequestration and reducing GHG emissions, a land swap can improve the broader farm ecosystem. The living plants and roots in a pasture can increase water infiltration and help filter impurities out of water, protecting groundwater and nearby watercourses.  

The species diversity of a pasture helps increase biodiversity. Two organisms Living Lab – Nova Scotia is particularly interested in are earthworms and dung beetles. Earthworms would be present in a horticulture field, but likely in low numbers as they do not like soil disturbance. Dung beetles would not be present at all since there is no source of manure for them. We are monitoring the colonization and amounts of these organisms with the pasture installation. Both have the ability to pull the organic material in the plants and manure deeper into the soil, helping to stabilize and protect it. Their actions can also break up compaction and improve soil structure.  

Land swapping also benefits the livestock industry in Nova Scotia by providing additional acres to increase herd sizes. While the horticulture producers are giving up a field for a short period of time, if the pasture can increase soil health the field should be more productive into the future, helping with long-term farm sustainability.  

A concern raised by our horticulture producers was the chance that a pasture could increase crop pests such as wireworms. We are monitoring wireworm populations and the adult form, click beetles, through bait traps. Our first two years of pasture have not shown increased wireworms compared to fields that remained in the horticulture rotation.  

Each of our pastures are different, as they had to suit the needs of the field and the producers. Two of our pastures are grazed by cattle and one by sheep. These differences can make comparisons between the fields difficult, but it is important to show that this practice can be used in a variety of situations.  

Clear expectations and responsibilities need to be established between the two producers. Everyone needs to know who is responsible for livestock health, ensuring water access is maintained, fencing installed, etc. to avoid conflicts.  

The NSFA is pleased to be working in partnership with five farms in Nova Scotia to develop and implement the land swap initiative. Farmers have been active collaborators throughout the project, seeding fields, installing fences/water systems, and providing shelter for the livestock. Thank you to Taproot Farms, Melvin Farms, and Websters Farm for co-developing, testing, and evaluating these BMPs in their crop rotations, and to Hidden Creek Farm and Kanfield Farms for providing the livestock to be grazed in pasture and for co-developing these BMPs.  

Thank you to Dr. Paul Manning and his graduate students at Dalhousie University who have been working on dung beetles and earthworms (in collaboration with Dr. Erin Cameron at Saint Mary’s University) at our fields. Thank you to Dr. Nancy McLean, also of Dalhousie University, for her help in pasture species composition. Dr. David Burton’s lab and Dr. Derek Lynch’s lab at Dalhousie University is gratefully acknowledged for their role in analyzing the GHG samples and soil carbon samples, respectively.