Those of us who grew up with the old fashioned stone fruit orchards or vineyards might remember some of the traditional methods for protecting the ripening fruit from birds. Mulberry trees were grown on the corners of some orchards to keep birds well fed and less hungry for the ripe orchard fruit. Mulberry cultivars were selected to ripen just prior to the fruit within the particular orchards.
The trees were not there to produce fruit to be harvested like the fruit within the orchards was. Most, but not all of what the birds did not consume fell to the ground and rotted. Only small quantities of the overly abundant fruit was taken by a few neighbors who made jam or syrup with with it. Mulberries were a byproduct of the orchards that some put to good use just because it was available.
Decades ago, it was much easier to get a bit of fruit from neglected or naturalized fruit trees in rural regions and on roadsides without offending anyone. Isolated remnants of the old fruit orchards were common. American plum, which had been used as understock for orchard trees, had naturalized in some regions. For those daring enough to harvest them, so had Himalayan blackberry.
Even now, we can find a bit of fruit where do not expect it to be. A few plants that are grown more for their visual appeal can be surprisingly generous with their fruit production. Pineapple guava, which is now popularly grown as a simple evergreen hedge, used to be grown instead for its small tart guavas. Purple leaf plum, as it matures, may not be quite as fruitless as it is purported to be.
The difficulty with the more unfamiliar types of fruit is finding practical uses for it. The native blue elderberry makes excellent jelly or syrup, like black elderberry, but not many of us even know it is edible once cooked. Australian brush cherry, strawberry tree, English hawthorn and ‘Majestic Beauty’ Indian hawthorn, are never overly productive, but might sometimes make enough fruit for jelly.
Of course, no unfamiliar fruit or nut should be eaten prior to confirmation that it is safe for consumption.
Tony Tomeo 
Interesting, having seen a zillion Purpleleaf Plums- I have never seen any fruit on them. Difference West coast vs. East coast?
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I think the difference is in the cultivars and their age. Because almost all of the suburban development and landscape in between the towns of the Santa Clara Valley is relatively new I never see fruit on the the purple leaf plum trees there. The tree in my front yard (where I lived in town) was planted in 1959 or so, and was also a more primitive cultivar. As it got old and stressed, it started making fruit. Young and vigorous trees are less likely to set fruit.
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Those Plums were popular in Atlanta in the 70s and 80s – they get borers (I think) look awful and die. People quit planting them. Can’t remember any fruit.
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They could have been too healthy and too young, and then died suddenly before they got old and tired.
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Hi Tony, I had to check on the “Australian brush cherry” as I hadn’t heard of it. Turns out it’s what we call “lilly pilly”. You’d need to harvest an awful lot of them to make jelly, but if you did, I think the flavour would be interesting. Possums enjoy them.
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Yes, the lilly pilly! That is such an appealingly silly name. There are only two cultivars of a single species here, and they are not very prolific with fruit. The fruit is good, but not abundant. When I researched them online, I was surprised to find that there are cultivars that are actually grown for a bit of fruit. If there were not so many other fruits that I want to grow, I might try one of those cultivars.
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I have some interesting fruits in our garden: Serviceberry is edible, tastes and looks a bit like blueberry. Cranberrybush Viburnum is extremely tart, but some make syrups or preserves with it. I’ve never touched our Elderberries, black or red, but our Wild Currant is very tart but fairly tasty. There’s also Thimbleberry and Grey Dogwood. Almost all these fruits are mostly left for the birds – though squirrels snarf down a lot of them.
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Yes, you got some enviable sorts. Serviceberries are not native here, so must be planted. Blue elderberries are like black elderberries for us, but I would like to try black elderberry just to see how they compare. (I intend to wind a blue ribbon this year for my elderberry jelly.) Our currants are not worth the bother. I got a few today, but they are very sparse, and not well flavored. I sort of wonder how your thimbleberry compares to ours. Those in the Pacific Northwest are indistinguishable from ours.
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I’ve never eaten a thimbleberry, but people say they are insipid.
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Ours are insipid if not ripe enough, or insipid if too ripe. They are only good if just right, but are not really worth the bother of watching that closely. I suspect that they are better in the Pacific Northwest. Those who know them there like them, although they never gather enough to do anything with. I intend to cultivate them just because they grow wild her.
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