Date: Sunday, May 20, 2018
Think Soil Health — Think HABITAT
Aaron Clausen – Biologist, Pheasants Forever
Soil health is hot topic of discussion amongst farmers and ranchers these days. Thanks to a relationship between dedicated conservationists and forward-thinking agricultural producers, years of research into soil health management and sustainable agriculture have been incorporated into farms across the Great Plains. In many locations the moldboard plow has given way to no-till disc drills and stripper headers, and friendly debates about crop yield are now being matched by comparisons of soil organic matter content.
The USDA Natural Resources Conservation Services (NRCS), which has led the charge in working with agricultural producers to apply soil health principles on our nations’ farmland, advocates five soil health principles: ground cover, reduced disturbance, plant diversity, living plants year-round, and incorporating livestock. The goal in applying these principles on the ground is essentially to re-incorporate biological processes back into the ecological system and create a resilient and sustainable agricultural operation. This concept seeks to restore ecosystem functions from the ground up.
As an example, consider a wheat or barley operation in northern Montana where a crop is harvested every other season and the land is fallowed in the off-years. Following the NRCS soil health principles, this producer might reduce their fallow frequency to once every 3 years, or could incorporate a broad-leaf cover crop mix in the place of fallow. These actions keep the soil covered longer, increase plant diversity, and keep living plants in and on the soil. This allows soil aggregates to develop, increases nutrient availability, and facilitates beneficial microorganisms and insects. As ecosystem functions return, the producer may be able to reduce dependency on inputs of compost, fertilizer, or chemicals, which will increase their net profit. To incorporate the other soil health principles, this producer could further reduce tillage to allow soil aggregate formation and increase water-holding and gas exchange capacity, and incorporate livestock later in the season to accelerate nutrient turnover through their digestion while providing a modicum of disturbance.
Because the tenets of soil health advocate for restoring ecosystem function from the ground up, many of the specific conservation practices used to improve it are directly beneficial to wildlife. An ecosystem’s food web – particularly the microorganisms and insects upon which more well-known wildlife species depend – are bolstered when soil health is improved. Incorporating certain principles into an operation can simultaneously enhance soil structure, organic matter content, and soil biology while also increasing food and shelter availability for countless species of upland and grassland birds, as well as pollinator insects. Each wildlife species is particularly suited to certain types of habitat, and depending on the production systems there are several management practices producers might consider:
DRYLAND CROP PRODUCTION
Increase residual cover
Even a small amount of residue and/or standing grain can be very impactful in areas otherwise containing little food or cover. It is also useful for trapping moisture and increasing organic matter content in soils. This can be accomplished by increasing harvest heights – by either adjusting standard equipment or using specialized equipment such as a stripper header – or simply leaving a small amount of standing grain unharvested.
Fallow may be useful in arid areas for moisture conservation, but it does little for soil health or wildlife habitat. Depending on your locality and agricultural system, consider experimenting with fallow replacements through reducing the frequency of summer fallow to every 3rd or 4th year, or by seeding cover crops instead of fallowing. This effectively protects the soil, increases biodiversity, and provides an additional source of shelter and food for wildlife.
This is especially important during the nesting season between April and June. Mechanical ground disturbance during this period can be particularly detrimental to not only unhatched eggs, but also nesting hens and fledgling birds. Depending on the type of crop, consider experimenting with reduced-till or no-till equipment in areas that have historically been subject to conventional tillage.
IRRIGATED CROP PRODUCTION
Operations that incorporate pulses or other crop types into small grain rotations will, over time, improve the soil microbiology and insect habitat. These benefits carry up the chain to bird populations, which are dependent on insect availability for their fledglings. Additionally, flowering crops are much more beneficial to pollinator insects than grain crops.
As in dryland scenarios, any efforts to limit ground disturbance will be beneficial both to soil structure and to wildlife as well, this is especially true for birds during the nesting season from April to June.
Incorporate field borders or buffers
For areas with lower production or odd geometry, field buffers or border plantings can be practical and ecologically beneficial. They trap moisture, contribute organic matter, and harbor beneficial insects for adjacent fields. In addition, buffers provide shelter and food sources for birds and pollinator insects in areas where they are often limited.
Identify areas to graze instead of hay
Haying removes biomass and nutrients from a system, and the process of haying can disturb wildlife and temporarily destroy their habitat. Grazing, on the other hand, returns much of the biomass and nutrients to the system, a windfall for soil biology. In addition, proper grazing management often results in a mosaic of different plant types, heights, and abundances, resulting in a patchwork landscape that is beneficial to a diversity of wildlife species in much the same way that native rangelands are.
Prescribed grazing plan
The key here is proper use of vegetation. Too much grazing disrupts soil aggregates, removes ground cover, and can result in denuded areas. Too little grazing can lead to monocultures of aggressive, rank grasses that inhibit biodiversity and tie up mineral nutrients. Both of these extremes are a detriment not only to soil health, but wildlife as well.
To continue with the above example, consider what replacing a summer fallow would do for wildlife on the landscape. It will provide shelter during nesting, brood rearing, and over winter. Continuous cropping would inevitably leave some grain on the ground, providing some food. To go the extra mile, a producer could opt to leave some grain standing which provides an excellent food source in the winter. Cover crops support an entirely separate group of wildlife in the form of beneficial insects, which themselves are a crucial food source for fledgling birds. It should be noted that some birds use land with very little cover – even bare soil – during certain parts of the year. But these types of areas are typically not in short supply on a landscape scale.
To put it simply: wildlife depend on soil health in much the same way that we do! Fortunately, implementing practices to build soil health yields a broad range of side-benefits, not least of which are improved habitat for wildlife and reduced financial inputs. There is a wealth of knowledge and precedent for implementing these practices on farms and ranches, and a great many conservation professionals looking to engage in these conversations with agricultural producers. Contact your local Pheasants Forever biologist, or visit an NRCS office, to find out more and learn about examples of these practices being applied in your area.