Sulphur Storms This past week has marked the start of pollen season in the mountain west. The white spruce, in particular, released vast amounts of yellowish-green pollen, coating every car, patio set, pond, and puddle. The railings alongside trails and even the surfaces of leaves have been covered in this fine powder. On my car, places I previously touched were dusted in a manner similar to fingerprint dust, leaving a yellowish outline of my fingerprint. Spruce are part of the Pine Family of trees, and all the members of this group reproduce in a similar fashion. Rather than using insects to pollinate the female flowers, they have evolved to use the wind. When a plant relies on something as random as a mountain breeze, it better produce a lot of pollen, and this past week we saw massive sulphur storms with clouds of yellowish pollen streaming from the trees and, in some cases, entire forests were blurred in a yellowish fog as the pollen spread its way across the landscape. Members of the pine family in the central Rockies include the white and Engelmann spruce, lodgepole, limber, and whitebark pines, Douglas-fir, subalpine fir, and the alpine larch. Every tree contains both the male and female cones with each taking a different role in the reproductive process. Male cones form on the lower branches while the female cones grow higher up. The male pollen cones grow at the base of the current year's new shoots in early spring, which in this part of the mountains is usually around the latter part of May. Different species produce different numbers of male cones, with a range between 15 and 140. Once the pollen has been dispersed by the wind, the male cones fall off the tree. Each male cone is a smooth, oval structure that contains dozens of spore-producing bodies called microsporophylls. When the cone is ripe, it releases tremendous numbers of tiny pollen spores. Each of these spores sport two tiny wings called sacci that help it stay airborne. When the sky turns yellow with this pollen, it's often referred to as a sulphur shower. Conversely, female cones grow very slowly and usually take several years to mature. This leaves cones in differing stages of maturation on the same branch with newer cones forming towards the tips. A first-year cone is soft and small, usually just a centimetre or two in size. Its main job is to collect the pollen and fertilize the cone. Second-year cones are much larger in size, more woody, but still green in colour. By the third year, the cones are hard and have turned brown and now contain fully-formed seeds ready for germination. Female cones are also much larger than their short-lived male counterparts. The cones form in either pairs or clusters along the branch and they vary dramatically in size. Lodgepole pine cones are only around 5 cm long, while the cones of limber pine can exceed 20 cm in length. Each cone is made up of alternating bracts and ovule-bearing scales. These scales accept the pollen and transform into winged seeds as the cone matures. Wind pollination is an ancient strategy and was utilized by the earliest of plants. It was the go-to strategy used by plants some 125 million years before flowering plants began to conscript insects to transport their pollen to other flowers. Even this was still 50 million years before the Cretaceous, the age of the dinosaurs, arrived. Almost all land-based non-flowering plants employ wind as their primary method of passing pollen from male cones to the ovaries hidden with the ovules of female cones. The randomness of wind as a transport mechanism means that if a grain of pollen lands on just the right spot, the female ovule needs to have some way to catch it before it blows away, They do this with a pollen droplet. This is a sugar-rich droplet exuded from the top of the ovule with the sole purpose of giving pollen grains a sticky