Choose colours lemon yellow, cobalt blue, quinacronine pink, sap green, neutral tint (or paynes grey which has a little more blue), beware the neutral tint will give a very strong dark colour. This composition uses a dry brush technique - use the brush parallel to the paper stroking the paint on using the whole brush, you should get a textured effect depending on the roughness of the paper.

 more tree 1    more tree 2    more tree 3
Roughly sketch the composition (how to draw a tree), paint clean water on the top left side and drop in blue allowing to flow. Mix blue and pink and stroke on top the right side leaving white textured areas. Add some green and use the same dry brush technique. If your brush is too wet remove the water from the base of the bristles.  

Pint in background hills loosly wet-in-wet.

Paint in the foreground with green and blue mixtures laeving the path. Paint the path with pink + green this makes agreat brown

 

 

Paint the shadows under the tree Add more darks to foreground very loosely

more tree 4   more tree 5   more tree final
 Start the trunk and continue with the branches moving outwards. Branches should not be too smooth (turn the brush as you paint). Colours and tones should change, the branch should get lighter as it moves away  

Add more darks to the foliage - you can use a dry brush or a sponge.

Add some fencing in the front

   Add more darks to the left bottom and when it is dry scrap off the paint with a sharp knife to give the pale branches