Corn

Wheat

Trees

The trees took a long time to get right. I used the Modular Tree Addon for the trunks. I tried using hair particle effects to grow leaves like I did for the corn & wheat but it didn’t look right. So I took a small patch of leaves and stamped it all over the basic shape by using the shrinkwrap modifier. Laborious, yes, but also precise and 100% under my control.