Ground preparation

One of our first activities out in our fields in the spring is spreading chicken litter to the fields that were in production the previous year.  Chicken litter works as a natural fertilizer, providing the soil with nutrients. 

After the chicken manure is cultivated into the soil, Barley is sown as the cover crop, helping with soil erosion and weed suppression.  Once mowed, the barley gets tilled into the ground, which provides additional nutrients and organic matter.  

When the ground is converted from cover crop into our planting rotation, that field will get sub-soiled, disked, cultivated and then culti-mulched before planting. 



Our seeds are acquired from all different sources. We are able to provide our customers with source identified seed.  Western Washington shrubs and hardwoods are tracked by county.  Conifers are tracked according to seed zone and elevation.  We also offer British Columbia, Eastern Washington, Idaho and Oregon seed sources depending on the species. 

Once berries are ripe and collected, they are lightly broken up with a blender. The blender is placed on a low setting, making sure not to blend too vigorously so that the seed coats are not damaged.  The seeds sink and the pulp is decanted, allowing the seeds at the bottom to be collected. 

Air suction is used to complete the final cleaning for some seeds.   The chaff is separated from the seeds by a simple labyrinth of PVC pipes, complete with flow adjusters and a hopper that are attached to a small vacuum. The simple method of using duct tape to adjust the air flow on the PVC pipe will make sure the air suction is only removing the unwanted particles, leaving the seed to fall into a bucket.  The seeds of a few species such as Paper Birch are lighter than some of the chaff, so the vacuum picks up the seeds and the chaff drops in to the bucket. 

Some seeds need tumbling in order to be extracted. These species are placed in closed sacks in a standard dryer with multiple tennis balls. The light rotation of the seed with tennis balls separates the seed, allowing it to be screened and ready for stratification. 



Most tree and shrub seeds are dormant when first collected. To break seed dormancy the seeds need a period of cold, moist conditions. Native tree and shrub seeds sown in the fall will naturally receive this conditioning period through the winter and spring. 

Conifer seed sown in the spring needs artificial stratification. These seeds are mixed in with Perlite, which is inert, heat treated pumice that retains moisture. The mixture is placed in a cooler for 30, 60 or 90 days depending on the species.

A few species are more difficult to germinate and need extended cold periods to break dormancy.  Some of these species are soaked in gibberellic acid, which is a plant hormone that reduces the amount of cold treatment needed.


Seed Sowing

 The Love Oyjord seed drill is a great machine for sowing seed. Each seed lot is weighed and the machine is calibrated to disperse the seed so that the proper seedbed density is achieved.  It sows the seed to the correct depth, in 8 rows.

Tree and shrub seedlings that receive the natural method of cold, moist stratification are sown directly into the field in the fall. The seed beds are top dressed with a layer of clean Red Alder shavings to protect the seed. 

Spring seed sowing takes place in April and May when the ground temperatures are warm enough. Species that were artificially stratified and species that require light to germinate are sown in the spring. Flash tape is tied to the irrigation risers to discourage birds from eating the freshly sown seed.



 Plugs for transplanting are propagated in a greenhouse and are received at the PMC in mid-March. Once the ground is tilled to perfection and the weather cooperates we can begin transplanting plugs for the following season's Plug-1 (P-1) stock.

Each year the amount of transplants we grow increases with demand. Species we offer as a P-1 include: Alaska Yellow Cedar, Douglas Fir, Noble Fir, Sitka Spruce, Western Hemlock, Western Larch, Western Red Cedar, and Western White Pine. Contract growing options are also available. 



The Plant Materials Center’s sixty acres is equipped with three wells that are all a part of our irrigation system.  Most of the soil on the farm is a nice, well drained sandy loam, which is helpful during the rainy months. Irrigation is necessary during the summer when we get warmer temperatures and periods without a great amount of precipitation.

Root wrenching is implemented during the growing months when the soil can become compacted, impeding root development. To reduce soil compaction, a horizontal oscillating metal bar is pulled just under the root zone. This method of lightly lifting the seed bed to aerate the soil gives the roots more space to easily develop. 

The same piece of equipment that is used for root wrenching is used for root pruning. The metal bar is replaced with a sharp thin blade.  The blade is pulled, oscillating horizontally at a set depth, depending on the species root depth at the time of pruning. The sharp edge of the blade slices off the very bottom tip of the root, which causes the root to become more branched and fibrous, creating a new location for additional lateral feeder roots to develop.



Each year, harvest begins when the plants have received 300 to 400 hours below 40 degrees Fahrenheit. This is to ensure deep dormancy. 

Harvest typically begins in mid-December.  If there are frozen conditions, it is too detrimental for the plant material to be lifted. 

To make harvest successful we use customized lifting equipment.  The 2008 4x4 Kubota M105S with cab was special ordered for our needs. The tires are set at the width of our planting beds and at a maximum height for plant clearance. A special creeper gear was installed to allow for the slowest possible transplanting and lifting speed. 


The 2008 PTO driven Lundeby Plant Lifter was designed for our plant clearance and bed width. The implement is pulled behind the tractor and set to the optimal depth for each plants root structure. There are oscillating teeth that help remove the soil from the roots with the least amount of stress possible. The end result is clean bareroot plants that are loaded into totes and immediately covered with wet burlap to be returned to our packing shed for processing. 


Once plants are brought to our processing line in the packing shed, they are sorted based on size and counted to bundle amounts. They are sprayed with water to make sure the roots stay moist before they are root pruned to 10". The bundles are then banded together, labeled and placed in our poly lined paper bags. The bags themselves are labeled and placed on a cooler storage frame.


Each frame is inventoried and placed in the proper location in our cooler. The cooler is kept at 36 to 39 degrees Fahrenheit to ensure plant dormancy. Scheduled orders are built in advance using the large quantity cooler inventory and are organized by order in the cooler.