Covercrop, Fall
Our past implementation projects have been focused on agriculture because the majority of phosphorus and sediment flowing into Northern Lake Champlain comes from agricultural lands.
We believe that working with farmers to encourage adoption of improved field practices is the surest way to improve the quality of water coming off of agricultural lands– and thus the surest way to improve water quality in Northern Lake Champlain. This requires the person to person interaction necessary to encourage experimentation, and it requires the funding necessary to support that experimentation.
We have been working on ag practices for four years in the Rock River basin and have worked on projects with 75% of the farmers. We have been working for two years in the St. Albans Bay watershed and have worked with 25% of the farmers. However, not all farmers have participated year after year, for various reasons, and the majority of annual crop acreage does not yet receive regular covercrop coverage or other improved water quality practices, Much more to be done.
Examples of the ag practices that farmers have undertaken with FNLC support:
“Covercrop” is the practice that we believe delivers the best results for the dollar expended, and we put considerable effort into this practice in the first years of working with farmers under a series of state grants. When winter rye is planted immediately after corn harvest (late September/early October), the shoot and root growth protects the soil from erosion until spring planting (early May). In addition there are benefits for soil nutrition, primarily the addition of nitrogen, which is a cost benefit to the farmer. Depending on how the covercrop is terminated in the spring, there can be benefits due to increases in organic matter and soil tilth.
Covercrop, Spring
We work to promote “critical area seeding”– an example is to plant perennial grass in swales in annual crop fields that are prone to heavy water flows and erosion. These areas contribute a disproportionate amount of phosphorus and sediment to the streams and Lake.
We worked with a farmer on “interseeding of covercrop” while the corn was still young. In clay soils with a mix of silt/sand, the covercrop had very good germination and very good growth, with complete soil coverage. It did not appear that the covercrop growth had any impact on the corn crop. We believe that there is significant potential in using interseeding as a means to establish a strong covercrop that will truly protect the soil against erosion through the fall, winter and early spring. Plus the larger amount of organic matter will be useful for improving soil quality.
For several years we have supported the use of an aerator for incorporation of covercrop or for incorporation of spring manure. The latter practice allows the manure to immediately seep into the soil rather than sit on the surface and it provides less disturbance of the soil.
We have also supported manure injection as it leaves less manure on the surface and so less likelihood of run-off due to weather events. Injection also reduces the amount of nitrogen volatilization- the more that the nitrogen is retained in the soil the less that is necessary to be purchased as fertilizer.
A new practice is the construction of Water and Sediment Control Basins (Wascobs) as a means to capture phosphorus and sediment in a settling basin built in swales in agricultural land. During heavy rains the phosphorus and sediment are carried in water rushing down through annual crop fields. The Wascob holds the water and releases it slowly, allowing the phosphorus/sediment to settle to the bottom of the basin. This also keeps the water from rushing into streams, which reduces the amount of high-water erosion in the streams. Buffer areas are installed “upstream” and “downstream” from the Wasbob as an additional means of capturing/controlling the phosphorus, sediment and stormwaters.
We have worked with farmers on several other field practices which will improve water quality connected to ag lands. For more information please contact Paul Madden at info2FNLC@gmail.com
The above projects have been undertaken with the support of Agency of Natural Resources, Agency of Agriculture, many farmers and other partners/supporters of FNLC.
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Critical Area Seeding
Manure injection
Wascob
