Whatever it is, you better start removing it. Are all those small things in the final image seedlings? If so, herbicide (triclopyr) or hand pull soon! The larger multistem clump can be managed with a slight variation. Cut off the stems at a foot or so, then immediately paint with full strength triclopyr as is directed on the label. Triclopyr is an active ingredient which is more effective on woodies than is glyphosate, the latter in Roundup & more.

I am going CRAZY trying to find a color that works with my simple stucco (ranch?) house. The galvalume (silver) roof is new as are the patches of stucco where we took off outdated trim bands. I'm hoping a fresh pair of eyes can offer suggestions because I've googled inspiration pictures for a week straight til I'm blind. I'm not happy with any of the samples I've chosen. I've tried *SW Universal Khaki which I thought would compliment the silver travertine pavers (like above pic) but it turns an awful color outside. *BM Revere Pewter-to white/light. *SW Dovetail-turned purple same as SW Requisite Gray, SW Perfect Greige, and SW Versitile Gray. *Porter Antique Silver-purple, *Porter Stone Gray-to brown, don't like it. *SW Amazing Gray-to light? but so pretty. *SW Fawn Brindle which at times still has a lavender cast to it but not as much as the others, wish I could say I love it but I might have to live with it. *Porter Olive Gray (which is similar to my interior)and stayed pretty true outside it's a 90.3% match to BM Clarkesville Gray BUT what do you think? Similar green interior/exterior/landscaping/lots of oaks-that's a lot of green going on. The majority of homes I've driven around and looked at that have silver metal roofs are vinyl side and the stucco ones are two story with elaborate trim to contrast with the body color. I am not dead set on any color family I just want something that complements the roof and looks good with the surrounding oaks. Sorry so long and thank you for reading!

I cannot dismiss early stage gummosis by looking at the picture above. I think a local expert should look at the tree. If this appeared on my roses I would say it is the work of a sawfly but on citrus? In the meantime I would isolate the tree if potted, treat the wounds and the soil with copper and if more of it appeared I would cut off the affected canes making sure the wood exposed looks nice and healthy. To investigate further ones needs to look at the state of the foot below the soil so a little digging may be in order. The fungal disease called 'Citrus gummosis' starts at the root and foot but there are also other types of gummosis. Also take a look at this, paying attention to 'citrus gummosis' and 'Rio Grande gummosis' https://cals.arizona.edu/extension/ornamentalhort/plantprotect/citrusdisease.pdf

I take it back… it kind of looks like a natal plum that I found while looking more into the Apocynaceae family, as Jay sugggested. The leaves I see on mine are much more delicate, while the ones I am looking at online look thicker and more fleshy, but maybe that‘s just a matter of growing conditions?