In summary, Tall Rooted Spike (TRS) cuttings are very long live cuttings that have been grown in a nursery to produce a robust root system. As noted, the plants are grown from cuttings of the various native willows (Salix spp.), Black Cottonwood (Populus trichocarpa), and Red-osier dogwood (Cornus stolonifera) – all of which root readily from live stakes/cuttings if collected properly (and without the use of rooting hormone). For more about each species see Species of TRS Cuttings Grown.
Locally evolved species or varieties within each of these plant groups can be found throughout north America, and they are all key species for use in many ecosystem restoration treatments (see Why These Species). I use cuttings collected around the Kootenays of B.C., for projects in this area.
The root systems on TRS cuttings is grown within poly potting bags, positioned up on the stem using an air-layering technique. This allows for the formation of a robust root system, on a plant that is very easily lifted from the nursery. Generally, two sizes of potting bags are used, 1-gallon and 2-gallon.
This is a Black Cottonwood TRS Cutting.
The photo was taken at the end of July, already this plant has a well-developed root system (note roots growing out the bottom of the bag)
The live cutting was collected while still dormant in March of the same year.
TRS Cuttings are unique as they take advantage of years of woody stem growth that has occurred in the wild. This allows the production of large rooted stock in only one growing season. The woody stem makes the plants not only tall and rigid, but also allows for the creation of a spike at the base of the plant. This spike, used to anchor the stem, means the plants are incredibly sturdy and wind resistant in the nursery, and after planting. The relatively compact root system on TRS Cuttings is easy to transport and timesaving to plant. For more see Advantages and Uses of TRS Cutting
Depending on the type of site TRS Cuttings can be planted shallow or deep.
Shallow Planting:
On moist, weed-infested sites the great height of TRS Cuttings immediately places weeds in the understory.
Deep Planting:
On dry sites is possible to place the root ball on TRS cuttings at 1.5 m or more in depth – no problem burying the stem with these species. Roots will form all along the buried stem.
A great way to plant TRS cutting deep like this is to use a soil auger.
Note also here that watering tubes can be installed at the time of planting. These lengths of perforated poly pipe allow placement of water directly at the roots.