The forest management cycle combines decades of biological knowledge with technical advances in forest management. Our Forest Stewardship Policy reflects our commitment to sustainable forest management.
Long-term strategic harvest scheduling starts with the detailed inventory of our timberlands. The forest planning and inventory team oversees independent and audited annual timber cruising of tracts to measure timber growth, which is used to update standing timber inventory volumes. Standing inventory measurements are completed over an approximately five-year cycle in the South and a ten-year cycle in Idaho.
The estimated total volume of standing merchantable timber inventory is updated annually. Standing merchantable inventory means that the tree being measured has met the size, quality, and other characteristics of the regional market. The annual update reflects additions of young timber that has met minimum diameter requirements, growth of existing merchantable timber inventory, decreases of timber due to harvests, wildfire, or insects and disease, and the impact of acquisitions and divestitures.
Timberlands are managed using 50-year strategic management plans based on harvest schedule models. Timber inventory data are utilized in growth-and-yield models, which optimize long-term harvesting and forest management operations and project sustainable harvest volumes over the 50-year time horizon. The harvest schedule is performed every two years, alternating between the southern region and Idaho each year. Within the strategic harvest schedule model, timberlands are organized into stands by common characteristics such as age and forest management prescriptions. Each stand carries a specific soil productivity designation called site index, which is based on the height of the dominant trees at a specific age. The higher the height of the dominant tree, the higher the site index on that stand. Site index also enables the inventory model to capture the expected impact of silvicultural improvements such as advanced genetics or fertilization.
The long-term strategic harvest schedule uses the starting forest inventory of each timber stand and then incorporates forest management activities such as site preparation, planting, thinning, fertilization, and harvest. Areas that have harvest restrictions are identified, such as streamside management zones, so that the model does not include them for harvest actions. Using all this information and a yield table – a table of tree heights, diameters, and volumes for each stand over the next 50 years – the model creates an optimization matrix that “grows” and “harvests” each stand of timber over time.
The strategic harvest schedule model builds an optimization matrix that contains all the possible choices for each stand over 50 years according to defined management constraints, including not harvesting restricted areas and replanting or regenerating every acre harvested. The harvest model checks every possible stand activity and combination over the planning horizon and produces a detailed stand-by-stand harvest schedule that maximizes Net Present Value (NPV) based on starting stand structure, yields, product prices, management choices, and harvest constraints.
Foresters prepare five-year tactical plans of tracts for silviculture work and harvest based on the results of the harvest schedule. Foresters select the timing of treatments and harvest based on timber type, growth stage, markets, road access, weather conditions, and operability of the site. Tracts are then moved into annual operating plans and site-specific prescriptions are developed for each forest management operation.
Harvest operations are conducted in accordance with Company best practices, regulatory, and certification requirements that protect water quality, wildlife habitat, and worker safety. Logging contractors must be on an approved contractor list and receive annual training. Foresters monitor logging activity to ensure environmental protections are implemented and specific prescriptions for the tract being harvested are followed.
Following harvest, the remaining residuals, or slash, are treated as appropriate for the geographic region. In Idaho, slash is managed to minimize fire risk through installation of fire breaks, mechanical piling, and pile burning. Southern harvesting operations result in less slash at final harvest due to stand thinning techniques to promote timber yield, allowing slash to be mechanically spread back into the tract and returning nutrients to the soil. Following slash management, sites are often treated with herbicides to control competing vegetation in order to promote growth of seedlings.
During planting season in late fall or spring, contractors plant seedlings on tracts that were harvested 12-18 months earlier. A release herbicide treatment is typically applied to enable seedlings to grow above competing vegetation. Third-party nurseries grow Idaho seedlings with 70% of the seeds being sourced from our Cherrylane Seed Orchard. The species that is best suited to the site-specific location and elevation is selected for replanting. In the U.S. South, seedlings are purchased from third-party nurseries and benefit from generations of selective breeding to promote favorable growth and yield characteristics as well as resistance to disease and insects.
Foresters monitor the growth of the timber stands by conducting physical stand exams, as well as by using modern tools such as drones, satellite imagery and GIS technology. New inventory data is synthesized along with information about operational activities into the long-term harvest scheduling model.
Commercial thinning is typically required on stands in the South and on occasion in Idaho to reduce stocking density to improve stand growth and development. Pre-commercial thinning is utilized when the number of stems is high enough that diameter growth will be reduced to a level where it is financially advantageous to bear the cost to reduce the density of trees, increase diameter growth and reduce the risk of insect or disease entering an over-stocked stand.
After harvest, the forest management growth cycle begins anew. Our foresters pride themselves on the tracts they grow over their careers.
On our Idaho timberlands, nothing beckons the awakening of the forest to spring like the sudden bustle of tree planting season. In six to eight weeks, roughly 6 million seedlings are planted across 15,000 acres of forestland. Planting is the culmination of an 18-month process that involves planning, preparation, and the growing of seedlings in the nursery. The climate and steep terrain in Idaho force this uniquely compressed tree planting window. To ensure high planting survival, seedlings must be planted into moist, warming soils with adequate time to grow new roots and become established on the site before the inevitable summer dry-down comes. The logistics are challenging, yet our foresters, contractors, and support staff do an excellent job ensuring the planting crews are just behind the snow as it recedes up the mountains in the spring.
Seedlings for spring planting are grown at several different nurseries located throughout the Pacific Northwest and southern British Columbia. Over 90% of our seedlings are from first-generation tree improvement programs and more than 70% of the seed is sourced at PotlatchDeltic’s own Cherrylane Seed Orchard. Seedlings must be thawed and then shipped to our cold storage buildings. Thirty to forty deliveries are planned and executed to keep seedlings on hand for the planting crews while minimizing the time between thawing and planting to improve seedling out-planting success. Planting inspectors are on site at every planting unit to make sure the operations plan is followed and to sample planting quality. At the peak of planting season in early May, over 200 people are actively involved in the planting program with more than 280,000 seedlings per day being planted-over one square mile planted in each day! We recently under took initiatives to decrease seedling stock size to lower growing, transportation, and planting costs and to reduce the inputs per seedling, including water, energy, soil, fertilizer, and packaging. We plant up to 6 different conifer species. Every tree species has evolved to fill an ecological niche in the forest, and we match those attributes to the conditions of the planting site. Each planting site is reviewed by our foresters and the appropriate species are selected with multiple species often planted in one planting unit. This process bolsters the diversity and resiliency of our timberlands, minimizing risks from climate and disturbance. Idaho’s steep and variable terrain limits planting operations to manual hand planting. Planters use either a shovel or hoedads to open a hole to mineral soil in which the seedling is planted. Planters carry the seedlings in tree bags they wear via a belt and suspenders with seedling holding compartments located on either hip. Each planter carries between 220 and 300 seedlings at a time - approximately 35 pounds.
High-quality, detailed planting is critical to the growth and survival of the seedlings - a seedling planted with minor error such as a crooked root or one planted too shallow with the root plug exposed will not survive. The critical job of planting the seedlings is done by contractors that rely on H-2B temporary labor visas to staff their crews. Companies must go through a heavily regulated process to get approval for the capped number of visas available. This includes the demonstration that the jobs are posted and available to American citizens but cannot be filled domestically. If contractors cannot secure sufficient H2-B visas, the seedlings grown the previous year may be wasted, and reforestation that is critical for regulatory, certification, environmental management, and wildlife may be delayed. Planting crews consist of one foreperson and typically 14 planters. A tree planter averages 1,700 seedlings planted per day - that is one seedling every 3.5 seconds for 8 hours. The work is hard, but you will not find a more pleasant group of people to work with than those reforesting our timberlands. We’ve built long-standing relationships with many of the planting companies, with some working with us for more than a quarter century. Many of the tree planters return for many seasons to plant seedlings on PotlatchDeltic timberlands and it’s great to see familiar faces and build relationships year after year.
Tree planting is one of the most important investments a timberland company undertakes, setting the stage for the future and ensuring all the benefits that forests provide are perpetuated.
Every year in the U.S. South, we replant seedlings across areas harvested the previous 12-18 months. The primary goal of our reforestation program is to utilize the best planting stock possible. Our planting stock is selectively bred to achieve superior disease resistance, produce excellent form, exhibit high growth rates and be well-adapted to the local climate and growing conditions.
In Arkansas, we produce 30-40% of our seed at two PotlatchDeltic seed orchards. The orchards were established through a tree improvement co-operative in the early 2000s using parent trees with desirable characteristics. These orchards are open pollinated, which means pollen from any tree in the orchard can pollinate the seed. The seed-filled cones are harvested in October and are sorted and stored by family for form, cold hardiness, and growth. The remaining seed is acquired from third-party nurseries and comes from seed produced using open pollination and controlled pollination. Controlled pollination allows selection of both parent trees and provides additional improvement to planting stock. We do not utilize seedlings produced from genetic modification.
Seed is grown into seedlings at third-party nurseries. Seed is sent to nurseries in mid-February for a 45-day seed stratification process. The seed is planted in nursery beds in mid-April and the seedlings are lifted on an as needed basis starting in early December. Before lifting can occur at least 200 hours of chilling is required, where the ambient temperature is less than 32 degrees in the nursery. Seedlings are stored at 36-38 degrees to prevent freezing and to keep the tree dormant. The seedlings are then placed in bags or boxes for storage and transportation. All this careful handling is done to maintain healthy seedlings that will thrive when they are planted.
Planting season in the South starts in December and typically lasts 18 weeks, wrapping up by April. Planting can be accomplished by machine or hand planting. Machine planting is effective in challenging soils such as gravel, light rock, or deep sand. The machine planters are a 2-person operation and plant approximately 12 acres per day per machine. Hand planting is used on sites that have undergone a mechanical site preparation to create elevated beds. Planting is done by contractors who typically hire H-2B guest workers. These professional tree planters tend to return year after year and are highly efficient and skilled. Crews of 10-15 planters each plant up to 3,000 seedlings per day or around 10 seconds per tree! Inspectors stay close behind the planters to ensure quality planting performance and proper seedling density. Foresters conduct checks as the seedlings grow to track growth and survival.
We recently engaged trials with robotics experts at Treeswift to explore and test proof-of-concept for a novel approach to field inventory measurements to stay on the leading edge of developments in forest inventory technology. Though work on the project continues, approximately 200 acres of our Alabama timberlands have been scanned, modeled, and analyzed in the initial pilot study. Additionally, we have been an active collaborator in assisting Treeswift in its efforts to develop forestry-specific expertise so the technology can be better utilized for commercial forestry.
The robotics approach utilizes drones equipped with a suite of remote sensors to fly through a forest at both ground level and canopy level. As the drones are flying, the attached sensors extract data about trees and the forest. The drones have LiDAR scanners as well as high-resolution cameras that allow them to create a virtual three-dimensional model of a forest. These highly precise scanners allow the user to increase the accuracy and precision of individual tree measurements such as tree-diameter and tree-height.
An additional expected benefit of utilizing the drones is greater efficiency of inventory crews collecting forest measurements. Increased collection speed would allow the user to obtain more data, resulting in increased accuracy of forest-level and stand-level metrics such as basal area, volume, and woody competition. The drone-based approach to LiDAR collection is an effective way to utilize advantages of LiDAR-sensed measurements.