Wouldn't it just be regular weeping willow, then a seedling, and then trained to be a bonsai? Aren't all bonsai just 'regular' plants, and then trained to have to be bonsai? Sue...curious and lost as usual

How small is a small yard? My wife wanted a weeping willow, so I had to find a place to plant one.My parents planted one when I was young,and it was quite large 15 years later. The place I bought mine from say's it will grow 60ft tall by 40ft in diameter on a mature tree. That would mean you should plant at least 20ft from building or property line,or other obstacle. WW is fast growing so you will have to prune alot to keep it in check.It also is not long lived. If you prune to much it may not look much like the willow you love.On the other hand if you cut it down before it gets to big for it's area,you may get 20 years or more to enjoy it.Plus it may take 5 years under good growing conditions to give you any shade. just my opinion. lp

first... weeping willow is a nice park or golf course tree .. most of us would suggest no closer than 50 feet to a structure ... of course you dont say what kind ... so i generalize ... second .... you dont mention size .... and i am sure.. 5 feet is way over the top... maybe a foot for every inch caliper ... once extablished.. in a year for a willow .... you should never have to water it again ... first link is a plnating guide ... second link is a pictorial on what i call a moat for watering ... its a good idea for the short period a transplant will need water.. but most likely way over the top ... ken guide https://sites.google.com/site/tnarboretum/Home/planting-a-tree-or-shrub pictorial ... but i cant see the pix... and hoping they will show later ... http://forums.gardenweb.com/discussions/1827881/how-to-transpalnt-a-conifer-tree-huge-pix-post

I think you mean invasive :-) And neither is really considered an invasive species although both will have aggressively water seeking root systems. Plant far away from any septic system or underground sewer or water pipes.