|MadSci Network: General Biology|
Yes, they can be made to open up with heat. As you heat the pinecone, the moisture in the bracts or scales dries and the outside of the bract shrinks, opening up the cone. Many pines have evolved a mechanism of opening the cones only during a fire so the seeds will be dispersed when there is less competetion and high fertilizer available. If you try this, do it on an old cookie sheet in an oven on a low temperature setting for a while. The pine resin will soften and ooze out onto the pan and is difficult to get off. You can clean it with some terpentine. If you need more help, you may write me at The School Page. See the site for more information:
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