Small swale on a steepish hillside, planting out to trees and shrubs

They say swales aren't really for steeper slopes, which we have, but I am going to take a chance as we have very dry summers and I really need creative ways to trap water on our land. This small swale is maybe halfway down our property, dug in about 20 minutes, and intended to feed a bed of raspberries, sunchokes, plus new trees that I am planting out gradually. It's not truly a "swale" yet because it doesn't extend across my entire property, but let's call them "moisture sinks" that will hopefully provide extended moisture to the trees just downhill of them, and I am digging these wherever I plant new trees now - eventually I will join them up, although my land is all downhill and only about 20m across!