Acorn crop failure 2008?

[derelict]

Since the spring I have suspected that the local acorn crop would be seriously compromised following a massive caterpillar attack... however when I checked the trees last week I was amazed at how few acorns there are - a handful of trees had crops which I would regard as small to moderate. Three had only one acorn apiece (I was using binoculars to see the top canopies) and the rest were generally mildewed or literally moth-eaten some to the point of near-complete defoliation. Even trees which have churned out acorns year after year are devoid of acorns. The picture is from last year.

Is this just a local effect or is it observable nationwide? Are there any substantial acorn crops in England this year?




(I am aware that acorn crops vary from year to year!)

[Tormentil]

I once saw a programme about oak trees. One was completely de-nuded of leaves by caterpillars but the tree recovered and produced acorns later in the season. Apparently oaks are quite resilient when comes to attacks on it by insects.

[village wench]

Originally Posted by derelict

Since the spring I have suspected that the local acorn crop would be seriously compromised following a massive caterpillar attack... however when I checked the trees last week I was amazed at how few acorns there are - a handful of trees had crops which I would regard as small to moderate. Three had only one acorn apiece (I was using binoculars to see the top canopies) and the rest were generally mildewed or literally moth-eaten some to the point of near-complete defoliation. Even trees which have churned out acorns year after year are devoid of acorns. The picture is from last year.

Is this just a local effect or is it observable nationwide? Are there any substantial acorn crops in England this year?




(I am aware that acorn crops vary from year to year!)

Would this be the reason for all the absolutely tiny acorns round my way ?(west Cambs)
Whilst fungi spotting under oaks I noticed that almost all this years acorns are only one third to half the size of normal

[Gill Catton]

oak trees (and many other trees) work on cycles where some years they produces lots of acorns and some years very few and some years somewhere in between. It is thought to be an evolved anti herbivore strategy I believe, it prevents a population of squirrels or rodents of other acorn munchers from growing to a size where it always eats all the acorns. - By having starve years this then causes the acorn munchers populations to decline meaning that there's fewer of them to eat acorns if the tree produces a glut in the subsequent year.

Interestingly all the trees in a woodland seem to follow the same cycle so presumably it is climatically influenced or Terry Pratchett has it spot on and tree conversations are just too slow for us to hear.

Apologies if this is a slightly ropey description, it was something that I was taught at Uni which was a good 11 years ago now!

[Ruth Daniel]

Whilst out walking last weekend we noticed thousands of what I can only describe as Acorn "bits" all over the ground........it looked as if every Acorn on the tree had shattered somehow.

[tufftie]

Originally Posted by Gill Catton

oak trees (and many other trees) work on cycles where some years they produces lots of acorns and some years very few and some years somewhere in between. It is thought to be an evolved anti herbivore strategy I believe, it prevents a population of squirrels or rodents of other acorn munchers from growing to a size where it always eats all the acorns. - By having starve years this then causes the acorn munchers populations to decline meaning that there's fewer of them to eat acorns if the tree produces a glut in the subsequent year.

Interestingly all the trees in a woodland seem to follow the same cycle so presumably it is climatically influenced or Terry Pratchett has it spot on and tree conversations are just too slow for us to hear.

Apologies if this is a slightly ropey description, it was something that I was taught at Uni which was a good 11 years ago now!

Beech is another tree that does this and a lot of pine trees - which have resulted in squirrel population crashes in Scandinavia and I guess other countries too. It's a good description

HAve you not heard of Ents?!

[tufftie]

Originally Posted by Tormentil

I once saw a programme about oak trees. One was completely de-nuded of leaves by caterpillars but the tree recovered and produced acorns later in the season. Apparently oaks are quite resilient when comes to attacks on it by insects.

One oak tree can support over two hundred species of insect - so I guess over the years they must have built up quite a resilience to them. Some must, in some ways, be beneficial to them?

[KeenTeen17]

all the acorns I have seen have been small or mangled

[derelict]

Can I tactfully put this thread back on topic?

Originally Posted by derelict

Is this just a local effect or is it observable nationwide? Are there any substantial acorn crops in England this year?

What I would really like is for all you good people to go and look at your local oak trees and see whether they have any acorns on them and report back ... that way we'll all know the answer. Sadly there are no books that deal with the 2008 acorn crop... observation is the only way...

The squirrels should be feeding on them now, and they're a pretty good guide!

[ron1863]

There are lots on the trees up here but they are all tiny at the moment