May 2018

I hesitate to say it, but I think spring is finally here.  There are cowslips in flower at the end of Pett Road where it joins Rye Road; there are wood anemones and lesser celandine all along Rosemary Lane, and there are bees feeding and nest searching in our garden.

Buff-tailed Bumblebee - Bombus terrestris

Two species of bee have particularly caught my attention – the buff-tailed bumblebee, and the hairy-footed flower bee.  The buff-tailed bumblebee can hardly fail to grab some attention.  For a start, it is Britain’s largest bumblebee so the queens are really easy to spot.  If that doesn’t get your attention then the deep throaty buzz of its wing muscles certainly will.  There seem to be a lot more queens about this year.  Maybe that is because the difficult spring has delayed their emergence from hibernation, or perhaps they had a successful year last year meaning that more queens went into hibernation and, being well fed, more survived hibernation.  Hopefully that’s a good sign for the coming season.

Hairy-footed Flower Bee, female in unusual pose, tongue out and
grasping the leaf with her mandibles

The hairy-footed flower bee could easily be mistaken for a small bumblebee, particularly the females.  It is a solitary bee (which means it doesn’t form colonies) and the male and female are very different.  The female is completely black except for some orange hairs on her hind leg, whereas the male is smaller and mostly ginger.  One thing that sets them apart from bumblebees is their habit of hovering and darting around flowers, so if you see what looks like a small black bumblebee hovering by your flowers, it has probably got hairy feet.  (That’s not actually true because it is the male that has the noticeably hairy feet that gives the species its name.)  Just like bumblebees they love the flowering currant and dwarf comfrey that are in flower in our garden at the moment.

But to go back to the cowslips at the end of Pett Road – I’ve never seen them there before, or at least never noticed them there.  This may be because of seed quiescence or seed dormancy.  Seed quiescence means that the seed is too cold, too warm, or too dry to germinate so it will wait until conditions are right.  Also, it may not be in the plant species best interest for all seeds to germinate at the same time – some flowering earlier or later may make a better use of available resources, or maybe flowering next year would be better.  But seed dormancy is slightly different.  Some species coat their seeds with a tough waterproof coating which seems an odd strategy at first when seeds need water to germinate.  One reason this happens is to stop the seeds germinating in late summer or autumn which would mean that the plant wouldn’t survive to set seed.  The frost will shift the soil around the seed and grate away or soften the seed coating so that water can penetrate, at which point the seed is ready to burst forth when spring finally arrives. (The technical name for this process is stratification.)  If there is no frost or the seed is too deep, then seeds may stay dormant for many years until conditions are better for them.  Gardeners wanting to short cut the process have been known to resort to the freezer and sandpaper to get their seeds to germinate.  It makes me wonder how coconuts manage!