Have you never stood under a row of 10 or 20 metre pine or macrocarpa trees? There will be a strip of a metre or so of no growth and it slowly increases in dens

Have you never stood under a row of 10 or 20 metre pine or macrocarpa trees? There will be a strip of a metre or so of no growth and it slowly increases in density from there out until 3 to 5 metres out.