Is it just me? I have spent the best part of a year waiting for this moment when acers in the UK are normally dripping with seeds just waiting to be harvested and sown, but to my immense disappointment most acers appear to be carrying very few, if any seeds this year. Has anyone else come across this phenomenon and in particular in the UK and does anyone know of any reason why this can happen? Nicola
Almost all trees have 'off' years when they don't produce much (if any) seed, nothing unusual there. In this instance it is likely due to the cold, wet summer last year - the trees weren't able to synthesize and store up enough sugars to feed a seed crop. So it may be bad again next year. In areas where conditions are only marginally suitable for a particular species (e.g. at a species' upper altitudinal limit or the northernmost edge of its native range), seed production may only happen in exceptionally favourable years; this may be as infrequently as once every 10 or 20 years. With cultivated trees planted well outside their preferred climates, they may never produce any seed at all.
I have been picking & planting since October 1st and like you, Nicola, have been sorely disappointed with the low seed yield this Fall. Most of my trees - and trees at friends' nurseries where I pick - do not have seeds this year. Even some reliable producers have few. An occasional tree is loaded with trees; I have an Ichigyogi that has hundreds & hundreds of samaras but mostly it is a poor or very poor yield year. Last year, of course, was very productive so perhaps that has something to do with this years paucity.
Like Katsura says, last year was an exceptional year for samaras (you can see my post on this phenomenon at http://www.botanicalgarden.ubc.ca/forums/showthread.php?t=26576&highlight) It is common for plants in a year following such abundance to produce few or even none at all Mine have produced none at all, with the exception of Aconitifolium and Griseum)
I love Nature's irony. In a year of seed scarcity I found a Shishigashari tree loaded with samaras. For years I have looked for them in vein. Also, just today I saw some seeds on my large Red Filigree Lace which tree never has them and which cultivar is stingy-if not outright mean- about giving samaras. I had looked over this tree carefully several times recently and seen no seeds, yet today while watering I suddenly find several. Amazing.
what I was really shocked at this year was the bloodgood me and my father planted in late august producded a ton of seeds. I figured with it just being planted that it would not produce from the shock of the move and all. Of course I took all the seeds : )
