you shouldn't have it so his speed is set to 0. You need 4 hitTests, one for each side. code:
onClipEvent(load){
speed= 5;
}
onClipEvent(enterFrame){
if(Key.isDown(Key.RIGHT) && _root.bg.hitTest(_x+speed,_y,true)){
_x += speed;
}
if(Key.isDown(KeyLEFT) && _root.bg.hitTest(_x-speed,_y,true)){
_x -= speed;
}
if(Key.isDown(Key.DOWN) && _root.bg.hitTest(_x,_y+speed,true)){
_y += speed;
}
if(Key.isDown(KeyLEFT) && _root.bg.hitTest(_x,_y-speed,true)){
_y -= speed;
}
}
make a background movieclip with all your "bushes" in them named bg
what this does is check if the player CAN walk right, and if so, he does. Same for left, up and down.