Hi,
Under
General -
Forest Stats window you can check more details about those Forest objects and it should give you a hint, where the problem is. In case of this kind troubles, double check you are using under
Distribution Map -
Density values corresponding to your working units and model size. Also please check your limits of
Max items /
Max faces for view-port / render when as in case of big areas or high density you can reach these limits and you may need to pushed some of them up.
On larger areas, you should be using presets that are meant to cover a large area(s). These will create fewer instances and are less taxing for the renderer. For both the Lawns and Meadows presets you will see there are two versions for each type, one with a (detail) suffix and another with a (large) suffix. Unless you're filling a small area, I'd pick the
large ones.
If the problem persist, please feel free to save and
send us the your scene to check it here. Thanks in advance.
Best regards,