Day 282: I began yesterday's kayak trip with a visit to the Sundews, only to find that while some of them appeared to be in the flowering stage with white petal tips showing, none of the flowers was open. Closer analysis revealed spent blooms, the withered, browned petals visible above the calyces. Some of the older inflorescences demonstrated developing seed pods, and some younger stalks carried full cymes of unopened buds. The accumulation of evidence led to a conclusion: the little buggers had closed up for the night and would open later in the day. Early bird that I am, the proverbial worm wasn't out of bed yet. I did the only sensible thing: took photos of the various stages and then went off for a paddle on the rest of the lake. When I returned in the afternoon, I found several open flowers, and it was interesting to note that when a cloud drifted across the sun, they closed quickly, responding rather more slowly in comparison as they re-opened when the sun emerged.
Drosera rotundifolia (and indeed other Drosera species) presents a fascinating natural history. They thrive in an ecology where other vascular plants might starve, and do so by supplementing their nutritional requirements carnivorously. Additionally, they survive in low pH (acidic) conditions where soil is almost non-existent, their shallow root systems serving largely to anchor them in place. Their laminae (paddle-shaped leaves) are covered with gland-tipped hairs which secrete a sticky substance containing digestive enzymes capable of dissolving all but the exoskeleton of insects including gnats, mosquitoes, beetles and even damselflies (see yesterday's post) as well as arachnids. They prefer high-moisture conditions, often growing right at waterline. In winter, the laminae curl up tightly to form a basal rosette called a hibernaculum. This structure conserves heat and prevents the plants from freezing. It's the only phase of their life-cycle I have yet to photograph, but then, botany ain't for wimps.
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