Which are the biggest strobiles (cones)? How heavy are they?

Answer 1

I am not sure if they are the BIGGEST on the earth, but in CA you can find GIANT cones from the Coulter pine or Digger pine trees. These are bigger than a football and can weigh a couple pounds. I would never recommend sleeping in a sleeping bag or tent under one of these pine trees, esp when there is a lot of wind! There are so heavy and sharp (spines) that they could probably inflict a serious blow-wound that could possibly give a concussion, a huge bump or even kill. It would leave a serious dent on your car too and could probably even break a windshield of a car. The wood of the cone is very thick, dense and hard!

Answer 2

Efectively she is correct, it is Pinus coulteri

The Coulter Pine or Big-cone Pine (Pinus coulteri) is a native of the coastal mountains of southern California (United States) and northern Baja California (Mexico). Isolated groves are found as far north as the San Francisco Bay Area in Mt. Diablo State Park and Black Diamond Mines Regional Preserve. This erect, medium-sized pine prefers south-facing slopes between 200-2300 m elevation, and tolerates dry rocky soil. The tree most often appears in mixed forests. The species is named after Thomas Coulter, an Irish botanist and physician.

The size ranges from 10-24 m tall, and a trunk diameter up to 1 m. The trunk is vertical and branches horizontal to upcurved. The leaves are needle-like, in bundles of three, glaucous gray-green, 15-30 cm long and stout, 2 mm thick. The outstanding characteristic of this tree is the large, spiny cones which are 20-40 cm long, and weigh 2-5 kg when fresh. The wood is weak and soft, so that the species is little used other than for firewood. It is also occasionally planted as an ornamental tree in parks and large gardens.

Retrieved from "http://en.wikipedia.org/wiki/Coulter_Pine"