Tent caterpillar hatches correspond to the changing solar radiation levels caused by the varying Earths distance to the sun throughout it's astrological cycle. At the aphelion when the Earth is farthest from the sun the caterpillar populations explode and very little webbing is present - at the opposite end of the spectrum there is a large amount of webbing (protection from UV) and populations decline.
These changes in caterpillar populations effect bird populations which effect tree germination rates...in the long term it can impact fire rates, localized flooding... Tiny connections have a huge impact outdoors on local pest levels, precipitation levels and the like and some of these are functions of our position in space. Indoors though you really don't need to worry about it. Same goes for outdoors with modern irrigation, pest management, and nutrients.