The shrub shelter is complete! All you need to do now is lay "roofing" over the crosspieces, such as pine or other evergreen boughs. This roofing will bear the brunt of winter's ice and snow, instead of the branches of your shrub. Assuming you already possess the simple tools required for the project, you'll have a free shelter.
These same techniques, modified slightly, are useful for other applications around the yard. For instance, instead of building garden arbors with lumber, you can construct them in a rustic style with poles fashioned from saplings. Unless you're using cedar or a similar wood, such structures would, of course, be temporary. But they're sufficient to support annual vines, as when you wish to grow your own Halloween jack-o-lanterns or gourd birdhouses.
Those of you desirous of a shrub shelter but who lack a natural wood source do have the alternative pictured on Page 1: an A-frame made with commercial lumber. But A-frame shrub shelters are suitable only for small-to-medium-sized shrubs.