Golden Gate Gardener

The Demise of Our Apple Tree

I have written before that our apple tree was struggling. In 2017 it bloomed in the fall at the same time it was ripening the crop it set in spring, a sign that it is not pleased with our climate. It must have received enough chill in summer to think it was spring. 

Our apple tree in august of 2017, with blossoms and maturing fruit. 

The blossoms were fertilized and began to form new fruits. I pulled most of it off, thinking it would not develop well over winter and would put stress on the tree to be ripening two crops at once.

 Fruit forming into fall. (I had picked most of it off, but left these to see if they would ripen. These are not ripe at all; it is a peculiarity of this unknown variety to have a red flush when it is still not ripe.

The tree had had many problems in recent years. There had been scab, which causes surface blemishes on fruit if it damages it when near maturity. However, if the fruit is infected while it is young, it develops poorly. The infected place doesn't grow, so the apple is malformed. The remedy is to spray early with a wettable sulfur spray and to get rid of as many fallen leaves as possible. (I used to gather up as many fallen leaves as I could and take them to my community garden, where there is no apple tree and the leaves are a welcome amendment.) (Scab is caused by the fungus Venturia inaequalis. Copper sprays are also sometimes suggested for it, but I avoid copper because it is toxic and will build up in soils under treated plants.)

Here are our apples with scab damage. 

The tree also suffered from damage caused by woolly apple aphid. It looks sort of like mealybug., because it covers itself with a similar fluffy white covering. It lives among the roots, especially in winter, then climbs up the trunk to feed on the very young branches. If it feeds it forms knobs on the branches and new leaves can't emerge. I fought it in two ways: One was by putting up a sticky barrier on the trunk, on a piece of tape, to keep the underground aphids from climbing up in spring. The second was by spraying any I saw on the tree with 70% rubbing alcohol in a small spray bottle. I also cut out badly damaged branches. Over they years, I reduced damage and the critters only appeared occasionally. 

The alcohol treatment is not to be found as a recommended treatment. After trying a number of substances, I found that the alcohol seemed the best. It disolves the waxy, fluffy, white coating just as it dissolves the similar covering on a mealybug. I searched the tree weekly and sprayed any I saw.

Woolly apple aphid on an apple tree. These are at the base of a leaf on a twig. 

In addition the tree sometimes showed rosy apple aphids on some of its twigs. They look like a more normal aphid than the woolly one and deform the leaves. I followed frequently given advice to cut off damaged twigs, so the aphids couldn't spread to others.

A friend who was helping me with the tree pointed out that it was planted too deeply. She could tell this because there was no flare at the bottom of the trunk, as it entered the ground. She thought tree would probably die. I left the tree in because it made a lot of good fruit. It was planted 50 or 60 years ago and pruned so badly (or not pruned) by previous owners that it took us several years to bring it back to fruiting. 

However, there were these problems, and then, in 2023, there was no crop at all and several of the branches never even leafed out. It was clear that the plant was dying. We had it removed in the summer of 2024. Before it went down, I took a few scions, in the hope of propagating the tree by grafting it onto another tree or onto a new rootstock. They were mostly not very good scions, since the tree grew very little in the previous year, but I took some short ones and some year-old stems.

A friend, Malcolm Hillan, who teaches Horticulture at City College of San Francisco, bought some rootstock that is semi-dwarfing and will resist woolly apple aphids. Six of the ten grafts we made took, and I have 3 of them. 

Here are two of the grafted trees. They don't look like much at this stage.

Malcolm says that of the three varieties he grafted, this one is the only one that did not get powdery mildew--another disease common on apple trees. But since two apple experts have been unable to tell what variety it is, this does not help others seeking a powdery mildew resistant variety.

At this stage the plants are just "whips," single stems. When they are planted in the ground (mine will go in soon) they will get a trimming to get the first branches to form low on the trunk. The ones I don't plant right away will go into larger pots. 

Meanwhile, the stump, which the tree remover left long so it could be more easily pried out, developed, in January, after a rain, a hearty ring of mushrooms, which seem to be those of Armellaria, or honey mushroom, named for their color, not their flavor, though they are indeed edible if well cooked (though said not to be particularly good--I didn't try them). Armillaria mellea, also known as oak root fungus, infects most broad-leaved trees and will even grow on buried pieces of wood. It attaches weakened trees in particular.

 The ring of Armillaria mushrooms around the apple tree stump was big and hearty.

I picked one to see the underside and the stem. There are about 10 species of this fungus. The most common, A. melea, has the annulus (ring) on the stem--like this one, which is most likely that species. 

Well, I guess we know what, in the end, killed the tree, especially since the arborist said there was evidence of fungal rot on the trunk at ground level. The fungus mycelium, the body of the fungus plant can grow to 10 feet long, so I think I will plant the grafted apple on the other side of the garden, though the fungus is not likely to be lethal to healthier trees. 

I will try to post the planting and progress of our new tree.

New Zealand Spinach Lasagne Recipe

Last night we had a party at which we served, among other things, a spinach lasagne made with New Zealand Spinach. People enjoyed it, as have we and those with whom we shared it, when I have made it before. I thought I had put the recipe on this blog, but it looks like I did not. So I will try to do so now, though the only pictures I have so far are of New Zealand spinach. I usually make a half recipe, which makes enough for 4-6 servings, but you can make a full one easily. Just double everything (use two jars of tomato-based pasta sauce) and use a big baking pan. One egg will still work in the ricotta mix whether doubled or not. You may have to cook a full recipe up to 10 minutes longer.

Here is a photo of New Zealand spinach for those to whom it is unfamiliar:

The plant grows wild just above the beach in San Francisco, teaching us two important facts about it: 1. That it is able to grow in areas with a cold, windy, often foggy, and dry summer.  and 2. That it is a rampant grower, weedy, in fact.  

Happily, this plant can also tolerate heat, so it can be grown inland as well. and it is a much more succulent, bigger-leaved plant when it is grown in richer soil and with regular water.

The plants seems to consist of single long leafy stems, though when you take off a tip, to eat it, new shoots will form along the original stem, especially if it is growing horizontally or vertically, and stems will often climb upward, reaching through a trellis or over another plant, or over other NZ spinach plants, then hang downward at their tips. It blooms as it grows, with small yellowish flowers, and forms, first soft, green, immature then, deep brown, mature, hard seeds in leaf joints farther back on the stems. (These fall as soon as they are ripe, and reveal where they fell with new seedlings. You can basically cut off and discard some of the stems if they get in the way and pull extra seedlings and let the plant have space you don't need.)

To harvest the plant, I break off leafy stem tips, 3 -4 inches long. above the place where seeds begin to harden. (It is fine to have immature, green seeds on the tips you pinch off.) There will be up to about a half-dozen leaves on your harvested tips. You will need 30 or 35 of these tips to make a half-recipe of lasagne, twice as many to make a full recipe. 

To make  a half recipe of NZ spinach lasagne:

Set the oven at 400 degrees F. 

You will need:

A Tablespoon of olive oil or a little no-stick spray oil

Lasagne noodles (hard no-boil are fine, though you may need to parboil some of them so you can cut them.) You will need 6-8 noodles for a half recipe, depending on the shape of your casserole.

A jar or can of tomato pasta sauce, 2-3 cups (read the label so you can avoid ones with high fructose corn syrup in them.)

About 1 1/2 cups of steamed New Zealand spinach--wash it and cut each tip into about 3 pieces. It steams fast--in 5-10 minutes. Cool it before you use it in the recipe.

A pound (or a bit less if the container you find is a bit smaller) of low-fat ricotta cheese

An egg--or, if you have an egg substitute product with the cholesterol removed, use 2 Tablespoons of that

3/4 to 1 cup of coarsely shredded part-skim mozzarella cheese

1 cup and a little more Parmesan cheese

One fourth to one half teaspoon of ground nutmeg. 

Directions:

1. In a big bowl, mix the ricotta with the egg, most of the mozzarella, and most of the parmesan, and the NZ Spinach, leaving a bit of mozzarella and parmesan for putting on top.

      2. Grease a baking dish.  The one I use is about 8 x 10" (inside measure) and about 3"inches            deep. It is important that it be deep, because you are going to put several layers in it. 

      3. Add a bit of pasta sauce to the bottom of the dish and spread it in a thin layer. Put a layer of lasagne noodles on top. My pan uses almost 2 noodles per layer (1 full noodle, with a half-noodle wide strip beside it, and a shorter strip of half-wide noodle at the end. (To cut the noodles, if they are the uncooked, no-boil kind, soften them for about 2 minutes in lightly boiling water, lift them out with tongs, put them on a cutting board and cut them with a knife or kitchen scissors. Put them in the boiling water one at a time to avoid noodles sticking together.) 

      4. Now that you have set the number of noodles you will need for each layer, make 3 layers as follows. noodles, a thin layer of pasta sauce, 1/3 of the ricotta/spinach mixture, 1/3 of the mozzarella,  a thin layer of pasta sauce. On the top, sprinkle a little shredded mozzarella and a little Parmesan. (Be especialy careful to not use too much ricotta filling or tomato sauce at a time so you have enough of them.)

Bake about 35 minutes. You want it to be bubbling, with the cheese on top melted and browning a little. 

You can refrigerate the lasagne, if covered well, for 3 days, or you can wrap it tightly and freeze it for a couple of weeks, then thaw it and heat it through.