By Jeff Rugg- Q: I would like some suggestions for what to do with all the pine cones that fall in my yard from the pine trees (other than just burning them, which so far, I have never done). I don’t want them to make more trees. Have you got any suggestions? These are not the really attractive cones that can be used decoratively. They are just ordinary, tight cones.
A: Pine cone is the generic term for the female seed-bearing structure of many evergreen conifer plants, such as spruce, hemlock, redwood and others. The male structure is often called the male or pollen cone, but it isn’t a cone. The male structure dries up and falls off the tree within a few weeks of releasing pollen.
The female pine cones take two to three years to develop and produce mature seeds.
The cone may open and allow the seeds to blow away in the wind, or it may remain closed with the mature seeds for several more years, depending on the species. Most pines develop and release seeds in two years. The bumper pollen crop from 2019 will produce seeds at the end of 2020 if conditions are good.
Each of the scales on the cone may develop two seeds, but if environmental conditions are not suitable, one or no seeds may develop. Potentially, each cone could produce a few hundred seeds, but most will be eaten by animals or not be viable.
About 20 of the nearly 120 species of pine trees develop seeds large enough to easily harvest and eat. Other species may have edible seeds, but they are too small or hard to harvest. Depending on what kind of pine trees you have, you may be able to harvest the seeds at the end of next summer. They will need to be harvested before the cones open.
As the cones develop, some may become too heavy for the branch they are on or the wind may knock them against a branch, causing them to fall off the tree. Green cones on the ground are not mature and have no value — except in the compost pile, where they will slowly break down.
Brown cones that are open have already released their seeds, but closed ones may still have seeds. The open cones can be used as mulch if piled up around the base of a tree or shrub. When stacked in an orderly manner, they can look good. Brown cones can be burned, but the resins in the cone may cause pops and sparks. They can also coat chimneys with creosote.
I have found that many pine cones are sticky with sap when first picked up off the ground. The sap collects dirt and turns your hands black. Before using the cones for an art project, the sticky sap problem will need to be solved. Place the cones on a paper towel, then place on a cookie sheet and put in an oven set to a low temperature (around 200 degrees Fahrenheit). After 15 minutes, the sap will have hardened into a glossy varnish that isn’t sticky and looks very nice.
You have to check the cones in the oven frequently. They will release a nice pine fragrance at first, but they can quickly turn dark brown and then black, while releasing a burnt-tree smell.
Cones that are not sticky can be used in a variety of Christmas and holiday decorations. They can be slathered in suet or peanut butter and birdseed to make a bird feeder.
Dried cones can sometimes be crushed under foot or run through a chipper and turned into mulch, but there are not many good uses for large quantities of pine cones. Most pines only bear bumper crops of cones every four to six years, so most of the time, you won’t have too many.
Email questions to Jeff Rugg at email@example.com.