That's a lot of land, you need to consider what portion of your total land that is, what uses you would like for it, and how much time you would want to spend maintaining it. You could terrace it with concrete mortarless retaining wall blocks and get more use out of it for growing shrubs, trees, blueberries, etc. You could make it a rock garden and grow dainty rock garden plants. I have a bank I got tired of weed whacking so I planted a number of aggressive spreaders on it to fight it out. It gives a varied appearance and interest at different times. I used- *Symphytum grandiflorum, groundcover comfrey, tubular pink to blue to white flowers in spring, very tough even for dry shade, sun, spreads fast, WILL overcome all weeds, impossible to remove. *Geranium macrorrhizum, very tough, dry shade, sun, pink flowers in spring *Hypericum calycinum, yellow flowers, spreads, tough, sun-shade Some other possibilities are heather or oregano. I also have thymes on a dry slope but some get woody after a few years. Oreganos come up from the roots, die down in fall leaving brown stuff to remove, but at least don't get woody and require pruning. I've seen slopes with an assortment of heathers, they take poor dry soil and spread out into mats. Different ones bloom at different times. I haven't noticed any drawbacks on mine or pruning requirements. I think some people mow them after bloom. I like to kill weeds over winter with black plastic or newspaper, then the ground is all bare and ready to plant in spring.

Yes you are correct, I was thinking about the whole yard at once, and this is just too much for my little mind to figure out. I have finished the book and the answer is not on the last page! I do think permaculture is more for bigger properties, than suburban lots. I do not have a zone 5, or a zone 3 or 4 for that matter. I guess I have a zone 1 near the house and everything else a zone 2. I figure if I won't want to drag the hose out that far, best to have a plant that can take care of itself. I have the veggie garden next to the house near the back door. I am also concentrating on my rain garden and keeping the trees in wood mulch. They look so much better since I mulched them up last summer. I think it is best for now to keep what I have healthy than to add a lot more plants that I can't keep healthy do to lack of time, water or mulch. I also took jekyll's advice and cut out to scale pieces of paper for future trees and shrubs. I also cut out future sizes of existing trees. This helps a lot in visualizing where trees are actually needed. I don't need as many new trees as I thought. Once the current ones fill out, I am pretty much all set. I do need shrubs though for wildlife perches and to shade off the tree trunks in hot Texas. I am going to in the future, get a few dwarf fruit trees for fun. I have selected apple, persimmon and fig. I may do annual papaya. It is too cold and wet in out falls and springs to bring them though winter. But I am not thinking about that now. I want to shrub up the current trees first and deck out my rain garden. The only thing in there now are some red cannas, and some Texas dandelions that I sowed last fall. The black eyed susan, the texas star hibiscus and the rain lilly seed that I planted last fall, did not come up. I will be receiving some rain lilly bulbs soon on a trade, to put on the not so wet edge of the rain garden. I will be putting basil and borage on the edge too. Come fall I will stick beets, rutabaga, and carrots on the edge of the edge. I have also planted cardinal climber on the hill coming up from the rain garden. They have not come up, so I may have to replant. I read to plant morning glories in winter so the seeds can crack and they will sprout. Maybe the cold weather that we have had lately have told them to not sprout yet. I think 1 or two are up though. I also have some blue eyed grass seed I think might work in there. Maybe I should wait to fall to plant them. I also would love to try some iris in there and then that is about all I have room for. This rain garden is a work in progress. It is mostly a canna garden now. The daffodils did even worse were I moved them too. Maybe texas is not the spot for daffodils.

There is no research done of this subject. I grow up in a large farming town in Indiana crop fields far as you could see. Before i was born ground water was determined too toxic to drink from herbicide run off. The town was granted money from the government to build a closed water treatment plant. All outside water was trucked in held in a storage tank for 72 hours while be tested. when the growing season was at full swing without notice water would be shut off for two days for treatment for herbicides. Main water lines was pex the return line was steel. No news was released how the herbicides was entering the system when we moved out of town they was replacing all return lines. So to use herbicides to remove a stump on a water line even if it is pvc or pex we have no idea if it can leak into the line. As the herbicides eat away the trunk it will be a holding ground for the herbicides to stay around the pipe longer.

When trimming, keep in mind that this is a matched set of “bookends,” so they should be exact, mirror image duplicates of each other as much as possible. I would think of the trimming project as a challenge … as if you were involved in a manufacturing process making a machine project on a lathe or something along those lines. It would not be at all detrimental to use a tape measure to double check dimensions for matching throughout the process. I would rough out the shapes of both before fine tuning either. The place to begin is standing back well away from them trying to envision what they are to become. If the shrub needs to be moved a little left, right or forward, this is the time to notice it and account for the adjustments you’ll need to make in the cutting. It really barely matters where the plant roots are located. If you the shrub to be 4” to the right, “move” it there with the cutting process. It’s important to envision the finished product before cutting because there is a substantial part of them that won’t get any cutting at all. If you just charged up on them and started hacking away, there’s a good chance you’d cut some wrong parts off. Since the pair of shrubs are matched, the first cuts to make should determine the height. (To match the pair, follow a line on the siding of the house as a guide. Don’t measure from the ground.) Keep in mind that you do NOT want to cut at the place where you envision the limits of the finished product to be (the red line in picture.) There are three reasons for this. As soon as you finish cutting the plant it’s going to grow and if you cut it at the finished height, in a short time it will grow too large. The second reason is because, even though you tried hard to make it a perfect shape, it’s not going to end up as perfect as you’d hoped for. Later, when you need to trim and try to perfect it again, you will want to be cutting only in the newer, softer, easier-to-cut foliage, rather than in the hard, sticky, woody portion. If you don’t cut a little smaller in the first place, you’ll probably end up where the next cutting has to dip somewhere into the woody portion of the plant again. This is a royal pain. If you make the plant a little smaller to begin with, it gives you a “cushion” against having this happen. In general, I find that people have a strong resistance to cutting the plant smaller (the blue line in the picture.) But do yourself a favor and get over this. If you mistakenly cut this plant to a stub, in two years you’d barely remember your error because it would be pretty large again. In cutting it just 6” less than you want it to be, in two months you’ll barely remember or notice that you did that. The third reason you want to cut the plant a little smaller than the “finished product size” is because the more foliage you remove from the top portion of the plant, the greater it is that you expose the bottom portion (the part that is undercut and desperately needs to grow) to more light and an improved chance of quicker growth. Between the yellow line (which represents the ground plane) in the picture and the shrub, there is nothing at all to cut … until you get higher up to the blue line. At this cavity at the lower portion of the shrubs, all the foliage will be left untouched so it can continue to grow as quickly as possible. The goal is to keep the upper portions of the shrub trimmed so that it shades the lower portions the least as possible. Even if you want the shrubs to be larger than what I'm showing, for now you should trim them as I'm showing because you're in a corrective phase trying to regain the lost lower foliage. In your second-to-last picture, it shows how a subordinate, adjacent shrub has encroached on the Yew, which is clearly the more important shrub. The lesser shrub should be trimmed such that this doesn't happen.