This same technique works for a mottled hillside too. Use the Freehand Tool to draw a gently rolling hilltop. Switch to the Pen Tool and click to add points for the three straight line sides. Apply a Fractal Fill using two shades of Spring green. You might want to export this sky and hill image as a TIFF or PNG bitmap and bring it into your favorite image editing program and add a Gaussian Blur to soften the shapes a wee bit. But wait? Where is the clover?