Puzzling Pictures 4: Under Wraps

Brian has been. I helped him on Thursday afternoon, but he worked all on his own on Friday. Just before he left, he asked me if I had an old blanket. "No, only some old towels." 

"Hang on a minute." He rummaged in the boot of his car, then came back with some blue, woollen material. His dog didn't seem best pleased.

"Got to keep the frost off it," he said, and covered up his handiwork, weighting down the blanket with a couple of stones.

"That's the most important part," he'd said earlier. "You've got to get that right, because everything else depends upon it."

What is it, and why is it so important? I wonder whether you can guess? Answer coming soon.

Here is part of the project's preparation.

 And here are some of the materials involved, waiting until he calls again.

 

 Meanwhile, in this wet weather, fungus flourishes on the old tree stump...

...but the snowdrops bud and bloom as they always do, bright and beautiful, whatever the weather.

 

To be continued.