It seems that most full grown iris larvae ascend to the tops before pupating, but they are annoyingly difficult to spot there (if you think watching the adults gives you neck ache, try scanning sallow crowns for pupae - you need to lie down on the ride and scan with binoculars, which seriously upsets dog walkers...).
Yesterday, two out of six wild larvae had already ascended, Aaron went up whilst I was watching, and the other three will probably start to pupate midweek. So, it looks as though most will have pupated by next weekend. At home, two-thirds have pupated and the others are pupating.
As Dennis's data indicate, the time spent in the pupal state is determined by June weather, and the insect can get trapped in the pupal stage by poor weather (I recorded pupae lasting 28 days during the Silver Jubilee Rains of 1977).
We have an anticyclone coming over this week, which suggests that we should start looking for adults over the weekend of June 18th-19th, but that might change as much depends on the second week of June.
There is, at this range, a serious chance of breaking the record for the earliest ever iris appearance, and the hunt is on. Early betting is as follows -
6-4 on Favourite: Bookham Common & Ken Willmott
3-1 Southwater Woods & Neil Hulme + friends.
4-1 Alice Holt & Tony Baines, Ashley Whitlock
10-1 Somewhere and Someone else...
It could be you... The Heslop Cup will be awarded to the winner.
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