The required seedling delivery date can be one of the most important variables in stock type selection (see Figure 4 for graphs of stock age and stock type by season sown for the 1997 planting season). All other decisions, such as ordering and growing, flow backwards from the anticipated delivery date.
Figure 4. Trends in stock age and stock type by planting season, 1997.
Planting should be planned for a particular date and adjusted for site and weather conditions. The seedlings used in different planting seasons are expected to respond differently -- spring-planted stock will flush; summer and fall-planted stock maintains budset. For spring planting, the actual planting date depends upon soil temperature, likelihood of frost, slope position and aspect, and block access. For summer and fall planting, the planting window depends upon soil moisture, likelihood of frost, and slope position and aspect. The timing of summer and fall planting is further complicated by the condition of the stock. Stock should not be planted unless it is sufficiently hardened-off.
There are five delivery dates:
The specific dates used in the different forest regions are indicated in Table 6.
The earlier the sowing request can be submitted,
For nurseries to have hot-lift stock ready for shipping by a specific date, each sowing request must be accompanied by a delivery date. Nurseries attempt to have the seedlings adequately hardened-off so that seedlings can be shipped by the chosen date.
Table 6. Planting seasons for biogeoclimatic zones by forest region. The dates used for spring planting are the most common for the biogeoclimatic zone in the region. Start dates will vary from year-to-year and depend upon climatic condition and site access. Finish dates for summer and fall planting are dependent on climatic conditions. Planting dates listed as possible are only being used under special conditions. If stock is generally not available for a planting season, it is listed as not available. Winter planting is often feasible in the Vancouver Forest Region in the southern most areas at low elevations.
|Cold-stored stock||Hot-lift stock|
|Biogeoclimatic zone/region||Start - Finish||Start - Finish||Start - Finish||Start - Finish|
|BWBS: Prince George||May 10 - Jun 20||Not available||Jun 21 - Aug 15||Do not plant|
|CDF: Vancouver||Feb 1 - Apr 30||Feb 1 - Apr 15||Do not plant||Sep 15 - Oct 15|
|CWH: Vancouver||Feb 1 - May 24||Feb 1 - Apr 15||Do not plant||Sep 15 - Oct 15|
|CWH: Prince Rupert||Apr 20 - Jun 20||Not available||Jun 21 - Aug 20||Aug 20 - Sep 20|
|ESSF: Kamloops/Cariboo||May 24 - Jun 20||Not available||Jun 21 - Aug 20||Not advised|
|ESSF: Nelson||Apr 30 - Jun 20||Not available||Jun 21 - Aug 20||Not advised|
|ESSF: Prince Rupert/
|May 24 - Jun 20||Not available||Jun 21 - Aug 20||Do not plant|
|ESSF: Vancouver||May 24 - Jun 20||Not available||Aug 15 - Aug 31||Sep 1 - Sep 15|
|ICH : Prince Rupert/
|Apr 20 - Jun 20||Not available||Jun 21 - Aug 20||Aug 21 - Sep 20|
|ICH: Kamloops||Apr 20 - Jun 20||Not available||Jun 21 - Aug 30||Not advised|
|ICH: Nelson||Apr 20 - Jun 20||Not available||Jun 21 - Aug 30||Not advised|
|ICH: Prince George||May 8 - Jun 20||Not available||Jun 21 - Aug 20||Not advised|
|IDF: Cariboo||Apr 15 - May 30||Not available||Do not plant||Do not plant|
|IDF: Kamloops||Apr 1 - May 15||Not available||Do not plant||Not advised|
|IDF: Nelson||Apr 15 - May 15||Not available||Do not plant||Not advised|
|IDF: Vancouver||Mar 1 - May 24||Not available||Do not plant||Sep 15 - Oct 15|
|MH: Prince Rupert||May 24 - Jun 20||Not available||Jun 21 - Aug 20||Do not plant|
|MH: Vancouver||May 24 - Jun 20||Not available||Aug 15 - Aug 31||Sep 1 - Sep 15|
|MS: Kamloops/Cariboo||Apr 30 - Jun 20||Not available||Possible||Not advised|
|MS: Nelson||Apr 30 - Jun 20||Not available||Do not plant||Not advised|
|PP: Kamloops, Nelson||Apr 1 - May 15||Do not plant||Do not plant||Do not plant|
|SBS: Prince George, Cariboo, Kamloops, Prince Rupert||Apr 15 - June 20||Not available||Jun 21 - Aug 15||Do not plant|
|SBPS: Cariboo, Prince George, Prince Rupert||Apr 15 - May 30||Not available||Jun 21 - Aug 15||Do not plant|
The spring plant is when the majority of seedlings are planted (see Figure 5 for graph of stock sown by season for 1997). Because most stock for spring planting is frozen or coldstored it can be thawed for delivery as desired. The start date of planting varies depending on thebiogeoclimatic zone (Table 6) and block access. Prolonged storage depletes carbohydrate reserves and reduces the vigour of seedlings. No planting of spring-delivered stock is recommended after June 21.
Figure 5. Allocation of requested stock by planting season, 1997.
Planting operations must take the thawing schedules of different stock types into account. Before delivery, the tops and roots must be evenly thawed, which takes about 5 to 10 days for container stock and about 3 days for bareroot. Once thawed, stock should be planted immediately. Spring-delivered stock rapidly loses both dormancy and hardiness; it will flush shortly after planting. In this condition, the seedlings are very sensitive to any stress (drought, frost, high temperatures) and very vulnerable to storage moulds. Planting delays, common for high-elevation sites due to late snowmelt, may make planting prior to June 21 infeasible. Under these conditions, consider the feasibility of a summer delivery.
Hot-lift spring delivery (coastal only)
Hot-lift spring deliveries of Fdc, Ss, Sx, Cw has been preferred for some coastal planting projects. This stock type is available as soon as site conditions permit and the stock can be lifted from the nursery. Never hold this stock in storage for prolonged periods once it has been lifted; plan on planting within one week of lifting (see Table 6).
Hot-lift summer delivery
All stock planted in the summer season will be hot-lifted. Summer-delivered hot-lifted stock has acquired a terminal bud and has some degree of hardiness -- it will not flush after planting, has lower requirements for water, and is better able to control moisture loss. However, summer planting stock is still very physiologically active. Roots are particularly active and vulnerable to damage. The essence of "hot-planting" is speed: lifting, packaging, shipping, and planting must be completed within a few days. Special care is essential so that active roots are not exposed to drying conditions or subjected to physical damage between the nursery and the site. Late June and early July delivery dates are typically more difficult for nurseries to meet than mid-July dates.
Choice of nurseries is important; choose a nursery that can reliably deliver this stock on time. Smaller stock types such as the PSB 410/412A are generally available during late June and early July. Specify your delivery date when ordering seedlings to assist nurseries in having your stock ready when needed (see "Ordering and Tracking Stock Types,"). This will assist the nurseries in having your stock ready when you need it.
Summer stock should be checked for succulence (see "Receiving and Handling Stock,"). If the stock has not fully hardened-off, the seedling will still have a high requirement for moisture, will handle poorly, and will not be able to control moisture loss -- it may perish quickly. Consider planting this stock later in the summer.
In the case of 2+0 outdoor compound-grown stock, hardening-off is weather dependent. An unusually cool wet spring will delay stock development. Although some stock can be held over for spring planting the following year, this is not recommended for the 2+0 outdoor compound-grown stock due to its size and potential for becoming root-bound and prone to disease.
Although this is the least used delivery date, it may be appropriate for coastal and coast-interior transition sites. It is generally not advisable for the interior, due to the high probability of frost heaving associated with early frosts. The stock is usually hardened-off well enough that it can wait at the nursery until suitable field conditions exist. This stock should be planted when soils are still warm and some root growth can occur provided that there is adequate soil moisture. This stock will have acquired more dormancy and will typically be hardier than early summer stock. If early snow or frost occur, this stock may have to be held over for spring planting but it can not be held over for summer planting! If site climatic conditions are still hot and dry, consider delaying the planting or plant north aspects and wetter sites before moving onto south aspects and drier sites.