(Altadena Mara) Peach trees don't last that long so are gone in around ten to fifteen years, from my experience at least. A foursome of plum trees also died over a ten to fifteen year period. One foursome of apricots had two trees die. One of them that was left was especially good so I let them grow full size. A three some of apricots is hard to keep cut back but doable. In a three citrus, one sapote cluster, the sapote has grown four times the size of the south placed citrus but is trained away from them so they still are growing and producing. I wish I had not planted the sapote there, another citrus on the same rootstock would have been better, but the sapote fruit are too delicious to remove it. I have several threesome of fig trees which aren't doing that well, compared to individual trees planted elsewhere, are about half the size, but are still producing a nice crop of figs. Banana trees make their own foursome, given half a chance and a little time. I would suggest that if you have a favorite fruit, plant it by itself. If you moderately like several different fruit, fruiting over time, plant a three or four cluster.

"But I do wonder why the tops of solid plank tables don't split more often than they do.... " They are not fastened in a way to restrict the movement of the top. There are metal 'clips' that attah to the bottom of the top and ride in grooves on the inside of the apron, 'Figure 8' (AKA 'double washer', and a lot of other names) that are fastened with 2 screws and allowed to twist slightly to allow movement, blocks of wood fastned to the underside f the top that ride in grooves in the apron (wood version of the metal clips), expanding tables with leaves just push part way open, and some others I cannot even remember at the moment. All these methods allow a large top (it moves as a single board) to move on the apron while remaining tightly attached. Wood does not move appreicably along the grain, but changes dimensiomn perpendicular to the grain. Chapter 3 of the Wood Engineering Handbook by the Forest Products Lab of USDA has a detailed explanation of wood movement (including an 'end view' of a tree showing how the wood changes shape). The book is online for free.

clarification...3-4 *mini packs of* seeds, not just 3-4 seeds. aka 3-4 separate mini packs, of different varieties of seeds, 20+ seeds to a pack, so 4 packs would be about 80 seeds! So for one 50 sent stamp, you could get 20seeds/1pk-40seeds/2packs-60 seeds/3pks or 80 seeds/4pks. Don't need that many? Take what you need, and use the rest to trade for something you do need or share them locally. I can drive & walk now, but It'll never work as it did before. I can drive, walk & not in pain, so I'm thankful for that. So, seeds can go out ASAP, now.

if the soil is decent and doesn't have too much fertilizer it very well could be too much water. looking at the picture it appears the leaves of the plant next to the tomato (corn?) also has yellowing lower leaves, which IIRC is one of those over watered symptoms.. if you continue to get rain perhaps put a tarp/plastic around the plants to keep water from continuing to soak the soil around the plants. BTW, i have the same variety of tomato (Bonnie big beef) here it is about 4 weeks old, very bushy with tons of flower, some of the tomatoes in the center are already 2-3 inches in diameter. you can't even barely see the 42 inch cage anymore lol... next year im going to go way bigger on the cage/support..