Species Descriptions: Terms
Here we describe what terms used to articulate site conditions mean.
We have done our best to describe appropriate site conditions for each species with a few concise terms. But keep in mind that no list of terms can fully describe all possible conditions. Most of the metrics provided here are based in our 30 years of ecological restoration experience. If you would like more information about a particular species’ needs, please contact us at Info@SoundNativePlants.com.
Term Definitions
Exposure
How much sun or shade a transplant tolerates—not an established, mature plant. Providing mulch and irrigation during plant establishment can push species’ tolerance to the sunny and dry end of the spectrum. Providing a shadier planting site minimizes soil moisture needs (for shade-tolerant species only).
Full sun means 6 or more hours per day of unfiltered sunlight.
Part sun means 4-6 hours per day of unfiltered sunlight.
Part shade means upto 4 hours per day of unfiltered sunlight.
Shade means little to no direct sunlight, but some filtered sunlight.
Deep shade means no direct sunlight and little filtered sunlight. These plants that thrive in dense rainforest understory.
Soil Moisture
What level of soil moisture a transplant prefers. A continuum from wet, moist, to dry. Some plants prefer year-round saturation and this is stated within the species description.
Wet/Saturated means that a plant prefers soaked or soggy soil at a regular intervals, with few and short dry periods. Sometimes total inundation. If a plant likes inundation, it is noted in the comments section.
Moist means that a plant prefers regularly damp soils, but not total saturation.
Dry means that a plant prefers arid soils. In our Pacific Northwest region, this often means soils that are very well draining that do not retain water for long periods of time.
Even with the correct soil type, irrigation is critical in most cases as plants establish, especially for conditions such as: spring installs, compact soil, little organic matter, high sun exposure, and species that suffer badly from transplant shock.
Salinity Tolerance
How much exposure to saltwater inundation or spray a plant can handle. Many plants cannot tolerate any salt. We understand that this is an important metric within our ocean-influenced ecoregions, specifically for shoreline restoration. So while it may not be applicable to many of the plants on our lists, it is a vital variable in PNW plant selection.
None means that a plant cannot tolerate any salinity.
Low means that a plant can tolerate a little salinity from salt spray or very small amounts of occasional saltwater intrusion. Plants with this level are those that live near shorelines, but not directly or regularly affected by saltwater.
Medium means that a plant can tolerate low amounts of regular salinity from saltwater intrusion and salt spray. Plants with this level are those that grow in backshore zone.
High means that a plant can tolerate heavy and regular salinity from saltwater intrusion or salt spray. Plants with this level are those that thrive along our shorelines or in estuarine areas.
Salinity tolerance data is gathered from the USDA Natural Resource Conservation Service Plant Characteristics database.
Fire Tolerance
Simply, how easily can a plant catch on fire. This is determined by the moisture and chemical content within a given plant. This metric is important within our changing landscape in regards to wildfire activity. Restoration, landscape, and individual practitioners should be wary of installing plants with no fire tolerance near buildings or other sensitive areas and thoroughly consider risk and local fire regimes when creating planting plans.
None means that a plant is easily flammable.
Low means that a plant has some, but minimal tolerance to fire.
Medium means that a plant has moderate tolerance to fire.
High means that a plant has good tolerance to fire, but can still catch in severe situations.
Fire tolerance differs from fire resilience, which describes a plant's ability to survive and recover after ablaze. The USDA Forest Service has a stellar database detailing a plant's ecology and regeneration regarding fire: Fire Effects Information System (it's a nerd's delight!).
Fire tolerance data is gathered from the USDA Natural Resource Conservation Service Plant Characteristics database.
Transplanting Success
Typical survival rate for a plant properly handled, sited, and installed at a restoration site. When preparing plant counts, do not expect more than 80% survival rate for any given species. If you are planting species with low transplant success, it's always a good idea to overplant and expect some die off.
High means that plant fatality will be minimal after transplant.
Medium means that plant fatality will be modest after transplant.
Low means that plant fatality will be moderate after transplant.
Growth Rate
How fast a plant typically grows after outplanting. Transplants from larger container sizes (5 gallon or more) usually take longer to establish and achieve the stated growth rate.
Rapid means that a plant will grow several inches to feet per season (depending on overall plant size).
Moderate means that a plant will grow a few to several inches per season (depending on overall plant size).
Slow means that a plant will grow mere centimeters per season (depending on overall plant size).
Form
Describes top growth as tree, shrub, vine, herbaceous perennial, or emergent (sedges, rushes, etc. that grow out of standing water), evergreen or deciduous, and gives typical maximum height at maturity. Root system description indicates erosion control potential, ability to spread by runners or rhizomes, and where and how far the established root system will reach for water and nutrients.
We organize plant form into three categories: trees and shrubs; perennials, ferns, and groundcovers; and gramminoids.
Check Out Species Descriptions by Form
Ferns, Perennials & Groundcovers
We discuss three types of carpeting plants: ferns, groundcovers, and perennials. Groundcovers and ferns may be perennial or evergreen. Perennials refer to the remaining flowers that bloom year after year.
There are three types of gramminoids: grasses, sedges, and rushes. The mnemonic "grasses have asses, sedges have edges, and rushes are round" is not 100% true, but it's a good place to start.
Trees are plants that typically have a single central stem or trunk, whereas shrubs are typically multi-stemmed. All of these plants take on different forms depending on the site conditions and maintenance.
