By Jonathan O.C. Kubesch1,2, Derek Hilfiker 1,2, Frank Reith 1,2, Dillon Golding 1,3 , Joe House4, Jenna Beville1, Peter Arnold1,5, and Forrest Brown1
- Virginia Tech School of Plant and Environmental Sciences, Blacksburg, VA
- Country Home Farms, Pembroke, VA
- Hoot Owl Hollow Farm, Woodlawn, VA
- Purdue University, West Lafayette, IN
- Arnold Classic Farms, Chestertown, MD
The vast majority of Kentucky’s population is not directly involved with livestock. However, backyard chickens have become a popular trend in recent years. Many people are raising chickens both for their fresh eggs and as pets. Some households even dabble in turkeys and ducks. While these birds can be a fun and rewarding addition to any backyard, there is some debate about whether or not they harm native plants and landscaping. In this article, we discuss both sides of the argument to determine whether backyard chickens help or harm native plants. Potential solutions and management ideas will also be presented in this article to balance your interest in native plants as well as backyard poultry.
Benefits of Backyard Poultry for Native Plants
There are several ways that you and your native plants can benefit from raising backyard poultry. In this section, we’ll review a few.
Pest control
One of the primary benefits of backyard chickens and other poultry is that they can help control pests. Chickens love to eat insects and other small animals that can be harmful to native plants. A few examples of this are chickens searching and eating beetle grubs such as June beetles (Cotinis nitida), common black ants (Lasius niger), and brown marmorated stink bugs (Halyomorpha halys). Removing these insects can be beneficial to desired plants. By reducing the number of pests in your backyard, your plants are more likely to thrive and grow.
Free organic fertilizer
Another benefit of backyard chickens is that they can provide a source of natural fertilizer. Manure is composed of ammonium, which is a volatile form of nitrogen, and organic N, which is stable but not immediately available. Poultry manure has one considerable advantage: it does not require commercial production and is a by-product of livestock production. Chicken manure is high in nitrogen, which is essential for healthy plant growth. By adding chicken manure to your garden, you can improve the soil quality and increase the nutrient content of your plants. This can help native plants grow stronger and healthier, making them more resistant to pests and diseases.
Poultry manure is a valuable resource that is often undervalued and subsequently misused in gardens and on farms. Fresh poultry manure typically contains 1.3% nitrogen (N), of which 55% is available for crop uptake (Zublena et. al 1996). Poultry manure also contains between 1.1-1.3% P2O5 (phosphate) and 0.5-0.8% K2O (potash). When using recommended poultry stocking rates, an average of 19 lbs N/ac, 31 lbs P2O5/ac, and 16 lbs K2O/ac are defecated in poultry manure monthly. If you were to assume a 40-lb bag of 13-13-13, a commonly used home fertilizer, costs $20, then accounting for the nitrogen contribution of poultry manures saves you $73 per acre each month on fertilizer. Scaled to your backyard, this might translate to $33 of nitrogen savings.
Of course, the nutrients from the manure need to be utilized, otherwise the full economic benefits will not be realized. Native plants are often slower to use nitrogen compared to introduced species, and so limited applications of poultry manure are preferable to larger deposits. To best utilize the manure nutrients, consider rotating poultry through garden or lawn areas, which will help nourish plant growth without the need for synthetic fertilizers. Backyard gardeners might prioritize getting their bird manure into vegetable gardens, then cool-season lawns, and finally into native plantings. Synthetic fertilizers are incapable of adding carbon to the soil as they do not contain carbon. When considering the immediate savings on fertilizer and the long-term increase in soil carbon, having poultry provides many other benefits beyond the meat and eggs produced.
Nitrogen cycling in mineral soils is a complex process with several pathways: plant uptake, soil-bound, aqueous losses via leaching, gaseous losses via denitrification, nitrification, and urea hydrolysis (Figure 1). Although manure and urea forms of nitrogen result in gaseous losses, utilizing litter as a part of a fertility regimen is a beneficial use of a by-product of livestock production. Additionally, using a mobile coop may be advantageous compared to stationary chicken coops, which often result in exposed soil. Exposed soil presents an issue when considering the advantages of poultry litter fertilization. When there is a lack of plant cover to protect the soil, there is additionally a lack of plant matter to incorporate nitrogen from poultry litter.
Improved soil organic matter
Poultry manures also provide valuable carbon (C) to the soil, something that inorganic fertilizers cannot do. Coops and runs full of wood shavings, sawdust, or other carbon sources can bind up the nitrogen in poultry manure and produce a more stable compost. Poultry manure can be a more stable form of fertilizer for native plants as the bedding material immobilizes nitrogen and then gradually releases the nitrogen back into the rhizosphere.
Plant roots can then uptake this nitrogen. This carbon is cycled by soil microbes into soil organic matter, which helps soil hold more water and provide more nutrients to plants, among many other benefits. While it is difficult to place a monetary value on the carbon additions of poultry manure, repeated applications will build up soil organic matter, saving you money in the long run from the countless benefits seen from increased organic matter. It should be noted that shavings are an additional cost to consider. This organic matter can also serve as an enriched mulch around native plant beds that can suppress weed seedlings.
Health and safety considerations
The direct application of fresh manure can also be detrimental to plants and their fruits. High levels of nitrogen, in the forms of urea and ammonia, and salts are often toxic to common vegetables and fruits. A direct application may quickly kill many desirable species. Conversely, manure with shavings will increase the amount of carbon present, which will immobilize nitrogen, making it less available to plants (Mahr, 2012). Bacteria harmful to humans such as E. Coli are often present in manure as well.
Composting recommendations vary, but it is generally accepted that poultry litter should be aged for 3-5 months and have reached a temperature of 140-160 degrees Fahrenheit. The USDA recommends waiting 120 days before eating crops fertilized with manure (Swanson, 2016).
Native plants for the backyard flock
Certain native plants can tolerate disturbance and high soil fertility, such as the rare previously federally-listed running buffalo clover (Trifolium stoloniferum). In another case, wild onions (Allium canadense) tend to grow rapidly, exhibit good health, and have increased numbers after a period of poultry foraging (F. Reith, personal observation). Across eastern North America, some native plants can even require regular disturbance to remain useful to wildlife (Table 1) (Kubesch et al., 2022; Brooke & Harper, 2018).
| Common name | Scientific name |
| Big bluestem | Andropogon gerardii |
| Little bluestem | Schizachyrium scoparium |
| Indiangrass | Sorghastrum nutans |
| Black-eyed Susan | Rudbeckia hirta |
| Maximilian sunflower | Helianthus maximiliani |
| Annual gaillardia | Gaillardia pulchella |
| Running buffalo clover** | Trifolium stoloniferum |
| Wild Onion | Allium canadense |
*Based on ongoing research at Virginia Tech as part of Bee-Friendly Beef; Kubesch, 2018.
**Running buffalo clover will be commercially available in 2027 in Kentucky. The authors anticipate that commercial availability will allow this species to serve as an alternate turf.
It is important to have woody plants that can benefit poultry year-round and cater to their needs. These species should provide shelter, protection, and serve as a food source. A variety of trees and shrubs can create layered diversity even across a “thin” woodland or a mixed range. Picture this as a layered forest garden for your flock.
Amongst the native species, there are a few that stand out and will serve your birds well:
- Mulberry (Morus spp.) is a native deciduous tree that most landowners probably already have on their property. It produces sweet berries that are loved by poultry and it can tolerate a wide range of soils and is easy to grow.
- Another great woody plant is serviceberry. Serviceberry (Amelanchier arborea) is another native deciduous shrub that can tolerate poultry well. It produces clusters of white flowers in the spring followed by blue to black berries in the summer.
- Elderberry (Sambucus spp.) is a small tree that you might already have due to its preference for rich soils. This tree would do well downslope in a backyard. It provides shade and serves as an additional food source.
- A tree that also might be found downslope is the dogwood (Cornus spp.) as it too thrives in rich, fertile soil. It will provide your flock with late season fruit to further diversify their diet.
- Another great tree, especially for the winter months, is the crabapple. Crabapple (Malus spp.) has a tendency to hold onto its fruit until late fall/early winter and gradually drop off.
- Further recommendations for shelter include eastern red cedars (Juniperus virginiana) and Willows (Salix spp.). Additional woody plant suggestions include various bramble fruits that are easily accessible to your birds. These include, but are not limited to blackberries, raspberries, and dewberries (Rubus spp).
Poultry can also be used to convert lawns into native plantings by destroying the existing vegetation (Arnold et al., 2022). This process is often unintentionally done when people first get into backyard chickens or poultry; however, it can be beneficial. Birds will forage and scratch through existing vegetation repeatedly when looking for food. Poultry preferentially eat broadleaf plants over grassy ones which can help to control the succulent broadleaf weeds around native plants. Furthermore, the continuous presence and addition of manure will also suppress and kill plants.
These actions combined will rapidly convert land to mud, dust, and manure when there is a large and stationary population. Poultry will not disturb more than the first 2-3 inches of soil generally, but nonetheless are an efficient form of “tillage” (Lee & Foreman, 2011). Such shallow tillage might be ideal for native plant seeding as it creates a fertile and loose seed bed. This scratching will likely be insufficient to plug plants. Controlled long-term presence of poultry may therefore allow for a natural, low cost, and easy form of native seed bed preparation.
Potential Harm of Backyard Chickens to Native Plants
Before you let loose a flock of chickens in your backyard, there are a number of things to consider. Let’s review a few.
Excessive disturbance
While backyard chickens can be beneficial for native plants, they will inevitably disrupt all plants at some point in space or time. They may eat plant leaves or their seeds, which can reduce the number of native plants in your backyard. Such losses are often unaffordable in smaller yards. Some native plants simply are not suited to regular disturbance. Furthermore, most natural ecosystems are not considered healthy when they are loaded with high levels of nitrogen. Overcrowded birds can kill trees and other ornamental woody plants by concentrating their manure around the main trunks.
Poultry will act according to their preferences. Most of their time will be spent around feeding or watering stations and in the shade; this will disturb the plants and ground around these areas the most. Waterfowl, such as ducks, will create muddy patches that may drown plants. Chickens will clean themselves and forage in certain areas, greatly disturbing the soil. Certain plants are also targeted more by certain poultry, which will change the ratio of native species present. It is therefore important to recognize areas and native plants that are sensitive to disturbance, and to manage poultry around them.
While the recommended trees and shrubs can tolerate poultry, they can still be susceptible to damage. Chickens and other poultry can scratch around at the base of trees and shrubs, damaging the bark and roots. Consider fencing off the area around young trees and shrubs until they are established. Mid-story and canopy layers should be regularly pruned to encourage further growth of the under-story. Recommendations range between 5-70% (Bright et al., 2011; McCord et al., 2013) canopy coverage for thin woodlands. Planning and experimentation are encouraged to determine what works best for your flock and management system.
Excessive fertilization
The nitrogen supplied by poultry manure can be a double-edged sword if proper conditions do not exist for plant utilization. One of the first chemical reactions from urea applied as poultry manure is the formation of ammonia gas (NH3). Ammonia is capable of burning plants that may result in necrosis of above and below-ground biomass; in extreme concentrations, plant death can occur. Therefore, when using poultry manure as a source of mineral nutrients, special care should be taken to ensure that NH3 formation will not be excessive.
Subsequent nitrogen cycle reactions can form the potent greenhouse gas nitrous oxide (N2O) and ozone-depleting nitric oxide (NO). In addition, nitrogen cycle reactions can form nitrate (NO3) and nitrite (NO2), which have the potential to contaminate above and below groundwater if leached through the soil profile or washed from the soil surface, which can be amplified in the presence of bare soil.
Diseases from backyard birds
Another potential harm of backyard chickens is the spread of diseases. Chickens can carry diseases such as avian influenza, salmonella, and E. coli, which can be transmitted to humans and other animals. If you have native plants that are used for food, such as berries or fruits, there is a risk that these plants could become contaminated with harmful bacteria. Chickens can also carry their own parasites and diseases if they are kept in the same area for more than a few years. As part of a native ecosystem, some of these diseases can end up in local songbird populations or transmitted to other backyard flocks.
What Can You Do to Protect Native Plants?
Once you decide you’re up for the challenge of raising both backyard chickens and a healthy display of native plants, you can take measures to minimize potential problems.
Set an appropriate stocking rate
There are several steps you can take to reduce the damage done to native plants by backyard chickens. First, set an appropriate stocking rate in space and time. Looking into the tubs of chickens, ducks, and turkeys at Tractor Supply might tempt you to eagerly purchase 25 birds, but for many backyards, this is likely too many. Historical research suggests that 100-400 laying hens or 100 turkeys per acre is the acceptable range for introduced clover and Kentucky bluegrass pastures (Kennard, 1962).
Kentucky’s average home lot is roughly 0.40-0.45 acres. A dedicated poultry hobbyist might be able to keep 40-160 laying hens or 40 turkeys (Pacheco, 2022; Home Advisor, 2018). For the extreme chicken fanciers in life, these numbers will come off like a blank check to crowd the backyard. However, these stocking rates assume the birds do not revisit the same area for 1-2 years. More conservative stocking rates can allow birds to stay in the same backyard for longer periods with fewer birds. A trio of laying hens or ducks will not have the same amount of scratching, foraging, and pooping as 100 birds.
Often there is confusion between stocking rate and stocking density. Stocking rate refers to the number of animals in a whole area for a single year (Allen et al., 2011). From the above recommendations, it is acceptable to keep 40 birds in a backyard for one year (40 birds per 1 backyard per year stocking rate). Stocking density refers to the number of animals in a specific area at an instantaneous moment in time (Allen et al., 2011).
From the stocking rate example and assuming the 40 birds can only access half of the backyard right now, then the stocking density might be higher (40 birds per 1/2 backyard stocking density)(Figures 2 and 3). Pastured poultry farmers (e.g. Joel Salatin, John Suscovich, and Justin Rhodes) move animals on non-native pasture grasses at extremely high stocking densities, but the birds are not in the area for a long time.
Use carbon-rich bedding
Secondly, consider keeping your chickens in a designated area, such as a chicken coop or run, to prevent them from wandering and damaging your plants. Permanent coops and runs often convert a yard to mud lots that pool water and smell atrocious. Some permanent yards are layered with straw or wood chip bedding or sand which is mucked out regularly. This soiled bedding can be used as a compost mulch as described above, which will provide your garden or lawn with much needed nutrients; however, cleaning coops is time-consuming and unpleasant. This manure issue is often one of the reasons why some suburban communities restrict chicken ownership.
Move your birds around the yard
Mobile chicken tractors or pens can be moved through the yard to spread the manure and foraging behavior more evenly throughout the yard. Chicken tractors are designed for short, introduced pasture and lawn grasses (2-4” tall; Salatin, 1993)(Figure 4). Portable electronet fencing can allow homeowners to move birds around over tall vegetation. The native plant backyard is likely better served by a coop on wheels or skids with a net fencing perimeter. Wheels are preferable in meadow or woodland settings because skids will catch on thatch and exposed tree roots.
Short duration occupation (<3 days) is preferable than longer durations (>14 days) because the longer birds spend at a location the more likely they are to harm plants (Figure 5). Short durations also prevent the buildup of pests and pathogens that harm poultry. Movement around a yard should be based on the intensity of the birds’ foraging and defecation rather than a set frequency. Consider these frequency guidelines for planning, but keep an eye on the condition of your native plants during daily chores (Table 2).
Figure 5. A mixed turkey and duck flock at the start of a 2-week stay in a portion of a non-native cool-season grass pasture in Pembroke, VA (March 11, 2023). This area is being considered for conversion to a native grass and wildflower meadow.
| Days of occupation or frequency of moves | Bird stocking density | Potential situation |
| 1 | 210* | *Native plant beds |
| 7 | 201 | *Native plant beds |
| 14 | 101 | *Native meadow or turf |
| 21 | 67 | *Native meadow or turf |
| 28 | 50 | *Lawn conversion |
| 56 | 25 | *Winter quarters in vegetable garden; lawn conversion |
| 365 | 4 | *Stationary fence in yard |
*This value is an exception to the other stocking densities based on an annual stocking rate of 100 birds per acre with a 1-2 year rest between visits. Do not stock animals more closely than this density. Never allow fewer than 8 square feet for layers, 15 square feet for ducks, and 18 square feet for geese and turkeys (Premier 1 Supplies, 2023).
Additionally, you may want to consider planting native plants that are less attractive to chickens, such as those with thick or spiky foliage. Blackberry and raspberry plants can provide food for songbirds as well as backyard poultry. Some situations may require building buffer areas with native grasses between waterways and backyard flocks, especially given growing concerns for the spread of avian diseases. This can help to reduce the risk of damage to your plants and minimize the impact of your chickens on the local ecosystem.
Poultry and native plants can co-exist
Backyard chickens and other poultry can both help and harm native plants, depending on how they are managed. While they can provide natural pest control and fertilizer, they can also damage plants and spread diseases. If you choose to raise backyard chickens, it is important to take steps to protect native plants and minimize backyard birds’ impact on the environment. By doing so, you can enjoy the benefits of backyard chickens while also preserving the natural ecosystem around you.
References
References for this article are hyperlinked throughout for easy access. If any links fail to open, please contact the corresponding author: Jonathan Kubesch, M.S. (jakubesch@gmail.com).
Acknowledgements
This work was supported by the pastured poultry producers of Country Home Farms. J. O. C. Kubesch thanks Sarah Grace and baby Kubesch [arriving August 2023] for their support with this article.
Resources
American Pastured Poultry Producers Association
Pastured Poultry Talk [Podcast]
Farm Marketing Solutions