Save a Forest in Southworth, WA

Southworth Forest Update:

Sitka Spruce Trees Prove Resilient in Southworth Forest

Posted May 26, 2024 by Southworth Forest

The 2024 crop of Sitka spruce from the annual King County Conservation District sale came bare root rather than as the plugs (small soil wraps) received in the 2023 sale. That means the trees will require a bit more transition time and look somewhat unhealthy, but all of the trees survived the potting process with significant soaking. These Sitka spruces will be installed in the forest during the 2024-2025 planting season.

As part of the Southworth Forest restoration project near the ferry terminal in Southworth, Washington, the dying canopy of big leaf maples and alders is yielding openings that are being filled by noxious, invasive species like Scotch broom and Himalayan blackberry. In addition to clearing these troublesome species, the restoration has included the reintroduction of a variety of conifers to the forest to establish a healthy blend of trees for tomorrow's canopy.

Survival rates amongst the conifer trees planted in the forest is highly variable despite each tree receiving the same compost and mulch treatments, deer protections, and periodic watering throughout the Pacific Northwest's recent dry and hot summers during their first three years in the ground. Trees in areas with more exposed, thinner top soils are receiving a 4-3-4 powder mix of nitrogen, phosphate, and potassium under the surface once or twice per year as well.

Of all the species of conifers planted throughout the Southworth Forest, the most reliable has been the Sitka spruce, which thus far has a survival rate greater than that of any other species, including the slower but resilient giant sequoias. The Sitka spruce are a distinguished native of the coastal Cascadia region, especially prevalent in the lower elevations of Western Washington and British Columbia. While they prefer full sun and moist soils, the Sitka spruce in this project have thrived even when placed in partial to fuller shade and in drier soils.

One notable aspect of the Sitka spruce has been its tolerance for bareroot transplanting. When purchasing large quantities of tree stock, it's not unusual to receive bareroot trees. Some species, like the Western Red Cedar, have a relatively poor survival rate when planted from bare root stock into larger pots or directly into the ground. The Sitka spruce, though, while often losing some of its trunk needles and looking relatively unhealthy the first year after bareroot transplanting, stands a much better chance of survival.

Of course, obtaining the trees as plugs in soil helps ensure much better growth the first year in the new home. The Sitka spruce stock purchased as plugs in prior years experienced very little delay in healthy upward growth the following year, and less water was required to achieve it. The bare root alternative is additional work up front, too. Since Sitka spruce roots spread outwards rigidly, larger pots or holes in the ground are required immediately, and the bare root plants will highly appreciate 4 to 6 hours of soaking in buckets prior to planting.

An immense challenge in the restoration project has been deer damage to young trees, regardless of fencing protection on each tree. The massive increase in deer population caused by the illegal 2019 forest destruction at the neighboring 11090 SE Southworth Dr. has led to consistent deer rutting (deer rub) in which the deer tear off the protective fencing and then rub the tree's bark, often killing the tree if completely ringing it. The very prickly needles of the Sitka spruces do not deter deer from rubbing on their trunks. Notably, however, the Sitkas attacked thus far have all survived, though one side of the tree's branches may die.

On the whole, Sitka spruce is a highly recommended conifer for restoration of Pacific Northwest forests. Don't be surprised if it performs better in relatively shady positions as long as proper acidic soil and moisture conditions are met. Be sure to protect your young Sitka spruces from deer with welded wire or other fencing around each tree if deer populations are a problem in your area. Once the trees establish, they can live upwards of a thousand years and reach 300 feet in height.

All the Sitka spruce trees closest to the neighboring deforestation violation have been attacked by the resulting increase in deer population, including this Sitka spruce of about 8 feet in height in 2021. It survived but lost its branches on one side. These trees had been individually protected by welded wire fencing that the deer first thrashed with their antlers prior to rubbing the trees. (2021)