Mould growth on timber

[cowboy25]

Hi I have some ply wood boards stored in my workshop I am going to use for the floor on my shepherds hut however the boards seem to developed mould on any surfaces exposed to the air. I had six of them standing upright and the ones in the middle seems to be ok. This has thrown a spanner in the works. I have removed the mould using either a belt sander or wire brush, but is the wood ok to use now? Should I apply some sort of mould killer? And should I then protect the wood with tung oil or varnish or something prior to using it for construction? I don't want everything moulding once the hut is made and standing out in the field.

 

Nb I'm quite surprised about this mould growth as no other timber in my workshop has mould on it, it's only the ply wood boards 

[JohnMo]

Give them a wash over with diluted bleach, to kill the mould spours.