Flood on the Hilltop
By definition, it would be pretty hard to flood me out on this hilltop. We are literally on higher ground than either our neighbor to the north or the neighbor to the south by at least 30 feet each. To the east and down the front slope it is perhaps 50 feet down to the road. And my back hillside is probably the steepest grade and it goes down perhaps 75 feet. Everything is relative and I recently went to someone’s house where they are on even more of a hilltop with even more severe grades in all directions. Naturally, I felt that I would not be comfortable being on such a steep precipice as theirs, despite the grandness of the views it creates, and yet I am always saying to Kim how much I like that we are on top of a hill the way we are. Now let’s add El Niño to the equation. Last year we were all about Atmospheric Rivers coming across the Pacific to visit us more than a dozen times with torrential rains, something that no one really warned us about. This year we have had warnings for months about El Niño and how it was going to produce a wetter winter for us and until last week, that seemed largely overblown. But now we have had wet weather for most of the past week and based on the emails and texts asking us if we have been the object of all the San Diego flooding that has gotten national weather and news attention, I think I can declare that El Niño is finally upon us.
The hilltop effect is such that the pooling of water is simply not something we need to worry about, so flooding in the traditional sense is not something we get up here. If water ever did gather anywhere on our property it would be down by the road since that is in somewhat of a saddle with the property on the far side rises up again by a small amount, making the road the low point. Last year I did see water spilling down our driveway onto the road, but it didn’t really gather there since it flows southward and downhill to the start of our dead end street. I will add that that flow ended up being unnatural in that there was a 600 gal/hour leak in my hot tub system that was causing it and that just happened to be during one of our first atmospheric river incidents. Otherwise, I’m not sure I would have seen moving water at all. From the road water seems to flow quite nicely down onto the large property of our neighbors who have avocado trees planted on their downhill 15 acres. It leaves a bit of erosion residue in the cross street at that point, but not enough to cause anyone to go out and shovel it away afterwards. After that, wherever the water flows it is well away from us and even our entire neighborhood. It’s good to live in a hilltop neighborhood like this because we do feel very flood proof in almost all regards.
But almost is the operative word. This is arid and hard-packed chaparral land with lots of rocks and boulders. Our house is built directly on top of granite for the most part, which is good from a stability standpoint. I don’t believe the base foundation could be washed away underneath the house, so we should never be subject to a big mudslide or one of those scenes where the house crumbles away into some raging torrent. These rocks up here have stood up to Mother Nature for millennia and will likely do so for many more. That is a comforting thought. The “almost” part of the equation comes in the parts of the property where my predecessor owners and I have tried to add soil and created plantable parts for a garden. For the most part, soil stays positioned in between rocks and rock gardens work quite nicely in giving gardens a hold on enough earth to sustain nice succulent growth. Succulents seem well-designed to lodge themselves in between rocks and I have several examples of quaint growth blooming seemingly from rock where they are really rooting themselves in the cracks where soil gathers. For the most part, my succulent gardens have prospered amidst the rocks and boulders and have mostly benefited from my irrigation of them. I have a far more lush property than anyone around me and get my share of ribbing for what people assume must be an excessive and profligate water bill. The joke is on them because this soil-amidst-boulder setting actually holds water well and my water bill is not so much more. But there is a point where that advantage ends.
When we have as much rain as we have had over the past week, those nice pockets of solid earth between the boulders can and do get over-saturated and that is where I run into trouble. Those succulents which grow to massive proportions, stretching the limits for scale as defined in my succulent books in terms of size parameters, create some plants that are simply pushing the limits of physics. They hold up just fine in normal or dryer conditions, but when it gets this wet they become precarious. In the front I have perhaps eight massive candelabra cacti that rise to as high as thirty feet in height and up to twenty feet in top spread. Their trunks are 15 or more inches across to support that size. The unfortunate thing about succulents when they get large is that they simply do not have deep or broad root structures. They store all their moisture above ground and that makes them incredibly easy to cut and /propagate. You really have to be a bumbler to not be able to take cuttings and get them growing. That is especially so in this climate since there is usually not enough moisture to even bother letting the stems dry out and scab over like the book says. In theory that serves to avoid disease and bugs from the moisture. The downside is that if you reckon that that a root ball on a normal tree or bush is about equivalent in size to the amount of plant above ground, you will be shocked to see how different that is with succulents. The root ball of a twenty foot high cactus that spread to 10-12 feet wide at the top might have a root ball that is 2 foot cubed. It doesn’t take much to bring that size plant down if the soil gets soft with rain.
That is, indeed what has happened this week in two places. In the front, a giant yellow/green Euphorbia Candelabra cactus on the northern side of the driveway keeled over from the rain. I suspect it was the combination of the softening earth at the base and the water weight on the multiple branches that was just too much for the puny root ball to hold up. It fell backward away from the driveway and into a large bush of Euphorbia Tirucalli or firs sticks and took some of that bush down with it as well as some surrounding jade plants. I have lots of fire stick and jade all around the property so that doesn’t concern me and is probably a good excuse to thin out some of vegetation in that area of the hillside. Nevertheless, I hate to lose such a large cactus, especially one very similar to the one I lost last year on the other side of the driveway due to root rot from my water leak. The silver lining is that this Euphorbia seems healthy and there are perhaps 60+ large 3-4 foot sections that can easily be repropogated. I have talked it up with my garden club pals and have takers for much of that for cuttings, well beyond what I will need for myself around the garden.
I also lost the 14 foot candelabra aloe that perched just outside our dining room window. That has a similarly small root ball and otherwise looks heathy, so i will just cut that off above the root line and have Joventino replant it right where it was…just a few feet shorter. I’m guessing it will take just fine and if not its a quick trip to the dumping cliff where I toss excess vegetation.
So, the flood report from El Niño on the hilltop is not so very bad after all. Nature has to do what it needs to do and man has to accept that trees and cacti don’t grow to the sky and need to clean the slate and start over every once in a while. It will give me something to do in the garden this weekend and that is never a bad thing to break up the rowing machine workouts.