Where are you out of? You look like you're in my area. Right from the beggining I was wondering what you were thinking and if you knew what you were doing. You can put more weight on it if you want to but what you will find is that it is still too small and will clump up with plant material and will even become less effective. As plant material is packed into it it will just slide right across everything. If you want to drag your road then you basically need a drag harrow at least three times longer than with weight on the front of each segment. You can buy attachment lengths to connect. A drag harrow like that will only work when the road is straight dirt or gravel and you use it to smooth out or grate your road. You can attach tires too it too! If you get enough weight on there or do it enough times hopefully it will start killing the plants to where you can start to get contact with bare ground.