Last week, the girls and I enjoyed a drizzly saunter through our woods. We were searching for ferns with sporangia on the undersides of their leaves, and returned home with them as well as other materials to study under the stereoscope (3D magnification up to 40X).
We recently studied conifers in our botany book. Pine cones open or close depending on the weather:
"The reason why the pine cones open when it's warm and dry is because that's a more favorable condition for the seed dispersal and germination," Read [a biology professor at Cal State] said.
Wet and cold weather would prevent the seeds, which are often winged, from spreading far enough from the tree to find a place to grow. Seedlings also wouldn't last long in winter rain or snow. (source)
This is how our pine cones looked on a drizzly, cool day,
after a one hour soak in ice water,
and then another hour in a 250 degree oven.
Easy, interesting, and educational--my kind of project!