An understanding of seed ripening characteristics is a qualification needed for any successful harvesting operation. Cone collections begin in the late summer and fall for most species. Collection of some fruit begins in mid-summer.
Many factors must be considered before harvest can be completed. Weather patterns, crop year and disease/insect damage are a few of these factors. If forecasting was completed, this would be easily determined.
For most species, it is recommended that the cones be collected immediately after the seed matures. Cones open very shortly after the seed matures, releasing it, making collection hard to complete. Weather again is a major factor concerning the ripening of the seed. See Figure 1, Fact Sheet 05 - Forecasting Collections, for a charted estimation for collection.
Conifer cones should be examined with a cutting test. This gives the collector an average of seeds per cone they collect which provides the yield. Also, some conifer cones re-close after the seed is released. This generally happens when it becomes rainy and cooler.
The attention should be focused on what cones are being collected. Avoid any old or immature cones. The old cones should be empty. Immature cones are low in viability and often produce deformed seedlings.
When collecting late maturing cones or serotinous and semi-serotinous species like Jack Pine and Black Spruce, cones may retain their seed for several years. This allows for more flexible collection dates. Older cones should be avoided (grey cones) because of low seed yields and viability.
When collecting Jack Pine, the characteristics to watch for are large, straight cones with no evidence of insect damage and are dark green or brown in colour.
A manual has been published for a more in depth description on collections of seed. Contact the Ontario Tree Seed Facility to acquire a copy of A Seed Manual for Ontario.
