Starting the Spencer Shadow Ranch

Doug and Sookjae McCarty purchased Spencer Shadow Ranch in 2014. Although it began as an investment opportunity, it quickly turned into what Doug now sees as his life’s legacy. Doug started spending more time on the land and studying permaculture design (a design framework for sustainable food production). Eventually, stewarding the ranch became his full-time passion and he never turned back. 

“When we took over ownership, the land was in bad shape,” said Doug. Parts of the land had been operated as a hay farm for years, relying on heavy inputs to stay viable. Other parts of the land were overgrown, not-recently-managed forests that posed a fire risk. The soil was compacted from heavy equipment and severely lacking in microbial life. 

The McCartys invested in livestock, believing that well-managed grazing would help improve soil fertility, structure, and water holding capacity, to support more production. “Divots from cattle hooves create thousands of mini-ponds that collect water,” explains Doug. “This helps water infiltrate slowly. Cattle also take forages and transform them into nutrient-rich manure that goes back to the soil and provides nutrients in a plant-available form.” Because of this, cattle can help improve soil fertility when rotated regularly and managed intensively. 

The McCartys now have a complete herd (calves, cows, and bulls) consisting of 140 head of Aberdeen Lowline Angus and Dexter steer—all grass fed and finished. To address the risks of high heat and limited water availability, the McCartys are practicing silvopasture, defined by the U.S. Department of Agriculture (USDA) as the establishment of trees, livestock, and forage on the same unit of land.

Climate affects livestock and adaptation strategies

Extreme temperatures

Both high and low temperatures can pose challenges for livestock. The USDA Plant Hardiness Zone for Eugene, Oregon is 8b. While temperatures can drop to 15 °F in the winter, they regularly climb into the high 90s in the summer. Since 1900, temperatures in Oregon have risen 2.5 °F. Temperatures are projected to increase another 4.7–10.0 °F by the end of the century, depending on whether greenhouse gas emissions are curbed or increased in the coming years. Much of the McCarty’s land is sloped slightly to the south, which exposes plants and livestock to even more heat. Cattle begin experiencing heat stress at temperatures as low as 75 °F, so Doug understood the importance of designing a system to address this risk. 

Photo Credit

Mitchel Davidovitz

Trees provide shade and relief from heat stress to livestock below.

One of the ways that the Spencer Shadow Ranch is managing livestock heat stress is by implementing silvopasture. In silvopasture systems, trees provide shade to livestock, reducing temperatures by up to 2.5 °F and reducing solar radiation exposure. This can reduce heat stress in cattle, resulting in increased feed intake, faster weight gain, improved fertility, and lower mortality rates. 

Trees also protect cattle during cold winter months. “The beauty of trees is that they provide shade and cooling in the summer, and they also provide protection from the worst of the winter,” explains Doug. Of the McCarty’s 340 acres, 120 acres are now managed as silvopasture, with native Oregon white oak (Quercus garryana) and valley ponderosa pine (Pinus ponderosa var. benthamiana) strategically spaced and integrated with pasture in the understory.

Reduced precipitation

Limited summer precipitation and regulations that limit irrigation are additional challenges for the Spencer Shadow Ranch. While Eugene receives around 46 inches of rain per year, it typically gets less than 5 inches from July 1 to November 1. Four months with limited rainfall can be challenging when trying to sustain cattle on pasture. Limited water may be even more of a challenge in the coming years. Climate change models project that summer precipitation may decrease in Oregon, and water stress will be exacerbated by increasing temperatures. The McCartys are addressing the challenge of limited water by planting pasture into thinned, wooded areas because the shade can help pastures maintain soil moisture longer by reducing evapotranspiration. This can enhance forage production during times of limited rainfall.

Integrating silvopasture 

Silvopasture is often established either by planting trees into existing pastures, or by thinning trees in an existing forest and planting preferred forages under the thinned canopy. [MH1] Achieving the right balance of trees and pasture is important; some shade from trees is beneficial, but too much shade can prevent pasture from growing. To achieve the proper canopy density, Doug thinned his forested land in a strategic way. Originally, the forested parts of the McCarty’s land held dense stands of white oaks (Quercus garryana), Willamette valley ponderosa pine (Pinus ponderosa) and Douglas-fir (Pseudotsuga menziesii). Doug started thinning the forest by first removing dead and dying trees. He also logged mature, economically valuable trees from an overstocked stand, including some older white oak, which he sold as lumber for flooring. Finally, he removed most of the Douglas-fir and cedar trees, because their dense canopies cast too much shade. These trees encroached significantly on oak and pin trees, reducing the amount of light that reaches the understory. Most of the healthy pines and oaks were left because Doug considers them “good neighbor species” that don’t compete excessibly with pasture for light or water. 

At Spencer Shadow Ranch, Doug opted to create islands of trees laid out in a patchwork design. In his design, there are 1–2-acre patches of well-spaced trees interspersed with 4–5-acre patches of treeless meadows in a grid pattern across 120 acres of landscape. Each paddock that cattle pass through contains both open pasture and stands of thinned trees. This allows cattle the freedom to access shade for relief from the heat when needed, and to access open pasture, which often supports more forage.  

Photo Credit

Mitchel Davidovitz

The landscape at Spencer Shadow Ranch has been intentionally designed to have patches of trees interspersed with patches of open pasture in a grid-like pattern.

By creating a patchwork pattern of treed areas and open grassland areas, Doug has also enhanced the “edge effect” on his land. In ecology, the edge effect is a phenomenon in which biodiversity richness increases where two or more habitats meet. “If you look at a forest ecosystem, the edges of the forest—where the forest meets another kind of ecosystem—are where most of the species interaction occurs,” explains Doug. “That edge is a hotspot for wildlife. A goal of mine with this silvopasture design was to create more of that edge effect on the land.” Although the ranch itself is only half a square mile, Doug has created roughly 20 miles of edge ecosystems with his design, which he says has allowed wildlife to flourish. 

Another benefit of this patchwork design is sustained forage production in each paddock at different times of the year. During summer, the growth rate of forage exposed to direct sun can be inhibited by high heat. When forage is grown under the partial shade of trees, however, heat stress can be alleviated, which allows forage growth to continue. In cooler times of the year, shade from trees can limit forage growth, so during cool months it is important to have some areas of pasture that are exposed to direct sun. By concentrating trees in patches and leaving some open pasture, Doug can extend the forage growing season using the same paddocks all year.

Managing with minimal inputs

While management is intensive, Doug has designed his silvopasture system to rely on as few inputs as possible. Rather than using herbicides to manage weeds in the forest, vegetation is mostly managed by cattle, which eat many of the undesirable species when rotated using adaptive grazing principles. After rotating cattle through first, Doug then follows with his herd of sheep, which eat the vegetation that cattle do not like, including poison oak (Toxicodendron diversilobum), hawthorn (Crataegus spp.), young cedar trees, and blackberry (Rubus spp.). 

Photo Credit

Mitchel Davidovitz

A skid steer with a log grapple attachment is used to remove trees to create more pasture areas.

Restoring the native oak woodland  is an ongoing project that is very labor-intensive, and that requires regular thinning with the use of specialized equipment. Doug cuts most trees with chainsaws and removes them with a skid steer that has a log grapple attachment that can lift up to 4,000 pounds. High-quality logs are sold, while dead and dying trees are hauled to a slash pile where they are burned. Once trees are logged, the remaining woody debris on the forest floor is cut up with a brush cutter. Finally, the ground is raked with a tractor, and vegetation is allowed to grow. Native grasses and clover come up naturally, but Doug also broadcasts native perennial grasses into these areas.

Rotational grazing is a critical part of silvopasture management to ensure that cattle promote soil health instead of damaging it. When cattle are rotationally grazed and the land is allowed to rest in between periods of grazing, animals can improve soil fertility, microbial activity, infiltration rate, and soil water holding capacity. At Spencer Shadow Ranch, Doug monitors pasture growth carefully to determine when it is time to rotate cattle to a new paddock. In his larger, 50–100-acre paddocks, the timing of these rotations is about every 2 to 4 weeks. In the smaller, 15–20-acre paddocks, cattle sometimes need to be rotated as often as every 3 days. Once cattle leave a paddock, that paddock is allowed to rest for a minimum of 40 days before animals are allowed back in.

Fencing is a challenge

Fencing infrastructure can be important both to conduct rotational grazing and to protect cattle from predation. Yet, fencing can be expensive and time consuming to maintain, and Doug has identified this as one of his biggest challenges. 

One of Doug’s land stewardship goals is to promote biodiversity across the broader landscape. He recognizes the role of wildlife in ecosystem health, and he welcomes diversity and abundance of fauna of all kinds—even predators like coyotes and mountain lions. Rather than kill these animals or eliminate their habitat, Doug’s strategy to protect his cattle while also promoting wildlife has been to exclude predators with multiple layers of fencing, including electric fencing and a perimeter border of taller nonelectric fencing. By having multiple barriers in place, Doug has been able to reduce the threat of predation without hurting predators. 

Eventually, Doug would like to invest in more fencing to establish smaller paddocks for optimized rotational grazing. Spencer Shadow Ranch’s existing paddocks range from 15- to 100-acres, but Doug’s goal is to divide the land into smaller, 20-acre paddocks so that cattle can be rotated through quickly at a higher stocking density. “The overall goal is to have 20-acre paddocks, each with roughly 6 acres of woods and 14 acres of meadows,” explains Doug. “This will allow enough canopy cover for weather protection, while providing enough open space to invite abundant grazing.” This type of rotation also promotes even pasture growth and allows each paddock to receive longer periods of rest between rotations. Paying for and maintaining fencing infrastructure is a challenge, but Doug feels it will be worth it. This infrastructure will support improved rotational grazing, which will benefit soil health, protect his cattle, and protect other wildlife.

Funding

The USDA Natural Resources Conservation Service (NRCS) helped fund much of Spencer Shadow Ranch’s initial forest thinning through a financial assistance program called the Environmental Quality Incentives Program (EQIP). Doug worked with an NRCS Technical Service Provider to develop a Forest Management Plan to guide decisions on which trees to thin and which trees to keep. Doug invested in equipment to implement the Forest Management Plan, and some of these costs were reimbursed through financial assistance from NRCS EQIP.

Report also posted: https://extension.wsu.edu/wrlp/silvopasture/casestudy/