Though it is a good practice to exhibit good housekeeping with our bees and adding ground cloth certainly adds to the neat appeal of our apiary, however this will not stop the spread of SHB, slow them down? Maybe. As Jim suggested, the larva (worms), will simply crawl to the edges and burrow into the ground where the ground will accept them. Keep in mind that the pesky SHB WILL travel up to 7 miles to enter your bee hives! Some say even further distances than that. I have enclosed a couple articles that may interest you. The first will be a video that you may seek to explore. Keep in mind that this will only work if you MAKE CERTAIN that ALL cracks and crevices are totally sealed from the top to the bottom of your hive and both top and bottom screens are advised in order for the bees to have adequate ventilation. It only takes a minute crack for these pest to enter our hives. I have not used either of the following, PVC portals or the guardian system, but plan to experiment with both this season, both myself and Mr Van, (van from Arkansas).
As Paus and sawdstmakr both advised. The Oil bottom tray will save your hives. Ask me how I know.
After losing a hive my first summer, I was able to save the rest, from sure overwhelming infestation and possibly total extinction all in my very first season. I have now been at it (beekeeping) about 21 months. Thanks to Jim, Paus and reinforced by others here, enlightening me of the oil pan method. I was able to save the rest of my hives via their methods.
Good Luck!
Phillip Hall
https://youtu.be/kFwYNqjdUIgHow to Save Remaining Hive from Small Hive Beetles ? Home ...
www.homesweetbees.com/q-a/2016/7/20/how-to-save-one...
Don't forget to inspect your other colony or colonies, small hive beetles can fly up to 7 miles in one flight. What To Do With Frozen Frames Once larvae has been killed through freezing, frames can be reused in most cases.