Will the leafs on my Oak trees reduce in size over time or do I need to do something to achive this?

Partial defoliation of your tree will help in 2 ways. It will not only create smaller leafs and internode's but will help with the branch ramifications. Only do this on healthy and mature trees, don't defoleat the hole tree at one time, you may get away with it for a year or to but it will weaken your tree so only partial at a time. After a few weeks you will see new growth.

Bonsai should always be in an almost root bound state by pot size. By controlling this, over time the tree will reduce leaf size. However, fruits of fruiting trees relatively stay the normal size of the fruit. Happy hunting.

Sleuth wrote:

Bonsai should always be in an almost root bound state by pot size. By controlling this, over time the tree will reduce leaf size.

Not good giving advise if you don't understand the basics.

www.evergreengardenworks.com/leafsize.htm

"Balance of the canopy to the root mass,
Age and density of the roots,
Level of fertility,
Presence or absence of hormones,
Level of light.
Of these five factors the first and second have the greatest importance for bonsai, but the other three also play a role." "Balance of canopy to the root mass" "first and second of greatest importance for bonsai" size of pot controls size of root mass buddy... straight from the site.

[quote="Sleuth" post=34463 straight from the site.[/quote]

Thanks for proving my point. Buddy.