Acacia Fruits - Why?

[Quelho]

Can someone please explain to me why Acacia's produce fruit.

[MORG]

[prier]

hahaha. genius!

[ubza_1234]

not sure exactly, but prob the same reason apples and mango and other fruits. :|

[incognito]

to produce seeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeds

[Heffa]

I cant find any photos but do you mean the grape sided green growth that infest the tree?

My Maidenii produces them, im pretty sure its some sort of parasite/fungal infection or something cause it doesn't ripen or drop off.

[tripsis]

When do Acacia spp. produce fruit? They produce pods, but I've not seen fruit. As Heffa said, do you mean galls?

[Quelho]

Yeah the galls. Plenty of places call them fruit, which is what has me confused. No seeds inside though. Additionally, the 'gall' growth grows from the plant (not like it is an insect nest), I couldn't find any worms/fungi etc inside the galls, and the galls texture is really well defined like that of a fruit... not like that of some gall growths on other plants.

So Heffa yes that is what I mean, the green growth attached by a distinct stem to the tree. I'm going to go and get some photos asap as Im not sure it is entirely clear which feature I am referring too.

[tripsis]

 

This will give you some info about them.

[ubza_1234]

i cracked open something like those lil fruit things once from an acacia and found a tiny lil worm in it. It wouldnt have feen 1mm long

[ThunderIdeal]

big nematode? i was under the impression acacia galls are fungal, there are probably several different types of acacia galls.

[ubza_1234]

i dunno what it was but the surrounding trees didnt have the lumps, only the acacias. Also, i only cracked one open and it had a tiny tiny worm inside about the thickness of 2 beard hairs and less then 1mm long.

[tripsis]

They would have been galls and it could have been a nematode or a small grub. How did it move? The great hydrostatic pressure inside nematodes makes them move in a very distinct way.

[occidentalis]

Wasps are a common cause of galls in Acacia

[ENtiTY]

Actually very few wasp cause gall on acacia. Mostly gall is caused by fungi. Wasps generally parasitise whatever is in the gall.

[occidentalis]

Really? There's a gall wasp named after Acacia longifolia:

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T3Y-48XKR9T-2D&_user=10&_coverDate=11%2F30%2F1985&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1580218926&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=583cbc1710c859334a86f7f83d744d3d&searchtype=a

[ubza_1234]

the grub i found didnt move much

[naja naja]

the grub is the larval stage of the wasp

[ubza_1234]

do you know what type of wasps lay eggs in trees? i'm guessing it's a non dangerous, native wasp?

[ThunderIdeal]

duno if they'd all be non-dangerous, i think they sting the cells of the plant to produce galling so maybe they can sting animals too.

[tripsis]

http://en.wikipedia.org/wiki/Gall_wasp

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T3Y-48XKR9T-2D&_user=10&_coverDate=11%2F30%2F1985&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1581939649&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=e29a62a3d123d0127b6aa5d77bedde25&searchtype=a

[Quelho]

Actually very few wasp cause gall on acacia. Mostly gall is caused by fungi. Wasps generally parasitise whatever is in the gall.

 

That is what I had seen. Galls without macro parasites. They were well formed etc. and I had suspected they may have not been galls for this reason. Even the colouring of some of the galls had no macro-signs of fungal infection. That being said, went and had a look at some today. These galls all have a hole, which is presumably for gaseous exchange. I have found plenty before without any holes, perhaps those ones were fungal or viral instead of hosting arthropods. The smaller galls here had 'grubs', presumably the juvenile arthropod, and the larger ones had the black arthropods.

Tripsis, that second link you put up looks promising. Perhaps these are those wasps or very similar ones. http://www.sciencedi...25&searchtype=a

Edited December 17, 2010 by Quelho