Found an escapee mandarin tree

I was riding my bike around and noticed an orange fruit in a tree along a railroad track I was crossing.  Upon closer inspection it appears to be a mandarin!  It's the last one and there's a few other's that have already fallen from the tree and laying in the ditch.  It's tasty! There's a garden on the other side of the fence where the tree is growing but the tree is on railroad property that is overgrown with a bunch of native trees and shrubs.  It looks untended.  To big to cover during the cold.  The last couple years have gotten really cold!  I live in central Texas and while it gets crazy hot here in the summer it also freezes in the winter.  We're a zone 8b and most citrus isn't supposed to make it through our winters.

The tree doesn't look like it was grafted.  An impressive trunk growing out of the ground without that tell tale grafting knot... or does that knot become unnoticeable after years?

I'm thinking I found myself a nice cold hardy mandarin that's volunteered itself.  I'm going to try to grow some of the seeds I got from the fruit. Mandarin's apparently come true to seed and produce in 4 to 5 years.  Wow.  Happy day.

i love finding random fruit trees, this past week i found a huge quince tree that we got about 40 lbs of fruit off, theres a pear down the road, a persimmon up the street. and many more all over the county. i have my weeks in the year to go pick fruits from certain locations. my fav is cherry season, theres a 40ft cherry tree on this hiking trail i know. in the spring i climb it and fill buckets of fruit.

Mandarin is one of the hardier types of citrus. I grow it in zone 9a. Not many fruit this year (maybe last year's very cold winter).

Calmondin is an incredible type of citrus that is even hardier. A friend in zone 8b has had one for many years. The fruit are small and sour, used like lemon and lime. Our tree is super productive, with one tree, we have far more than we can use.

I live in a zone 8b but also in the city so I imagine I'm pushing zone 9 with the city climate.  My neighbor has two very impressive grapefruit trees (25'+) just across the street.  Around the corner a neighbor has an even bigger grapefruit tree.  Around another corner a neighbor has 5 or 6 large tangerine trees.

I just planted 6 calamondin seeds.