Quick update. As per previous posts, I dug a total of 3 "hawthorns" (or so I thought!) one of these trees got the black bag treatment. The other two were left to the elements and hoped for the best.
At this stage all three have pushed leafs. It turns out that one of the trees was actually a Blackthorn or prunus spinosa. I didn't realise until after leaves were produced.
The hawthorn that got the black bag treatment initially thrived. It pushed strong shoots which was really encouraging. I was hoping to develop maximum roots before winter and all was going to plan. After a few weeks of black bag treatment, I I started introducing sunlight. It was actually kept in the shade but natural light none the less. After a few weeks of light it was moved into full sun. Bearing in mind it is Ireland and the full sun over the last few months has really been mid sun- at best! I kept watering the foliage to help keep the tree hydrated as the roots were yet to establish. Unfortunately, for the last few weeks I have been battling some type of leaf blight. They are drying out and crisping up. I have sprayed with fungicide every 8/10 days and stopped watering the foliage. I still don't have it under control. I'm still removing infected leaves. Hopefully the new leaves will be healthier.