How to get driftwood to sink?

[onesimus]

i drilled a hole in a big piece of red slate and screwed it to the bottom of a huge piece of driftwood,been like that 10 years now,used some type of chrome screw 3 inches long.

 

[Jkoziatek]

the slate idea is prob the best and most reasonable... only issue is if u decide to redo the scaping... if u want a less permanent way go with tying fishing stirng with to to a heavy rock.. i would avoid lead but thats my opinion.... and the burying under gravel also works too!... goodluck!