Fine hair-like thorns? Like raspberries? The blackberries in Griffith Park have the more traditional rose-like thorns. They grow in large tangled messes about 3 or four feet tall and however deep. Lots and lots of spider webs, too. It was probably not ursinus, I guess. I did some more researching... The Wikipedia entry on blackberries had some interesting background on the development of the thornless varieties. The thornless-erect varieties have been developed (primarily) at the University of Arkansas, and they share some common traits, including that they are "less vigorous" but tolerate cold better than the semi-erect varieties. (Navaho, Ouachita, Cherokee, Apache, Arapaho and Kiowa.) They propagate through root runners. Many of the Eastern semi-erect thornless varieties were developed through USDA-ARS in Maryland and were hybridized from the UK's Merton Thornless. "The semi-erect blackberries are thornless, crown forming, incredibly vigorous, and need a trellis for support. Cultivars of this type include the very popular Chester Thornless as well as Triple Crown, Loch Ness, 'Loch Tay', Smoothstem, Hull Thornless, Dirksen Thornless and Black Satin." Many of the trailing varieties have been developed though USDA-ARS's Oregon facility. (Black Diamond, Black Pearl and Nightfall as well as the very early ripening Obsidian and Metolius.) The erect ones tend to be the most cold-hardy, the trailing ones the least. I am having the greatest difficulty finding information about chill hours for blackberries. Not a clue to be found, anywhere. It would be nice to have all this in a convenient blackberry FAQ. I thought I researched the subject of blackberries fairly well before ordering the Arapaho, years ago. I've been patting myself on the back for being so thorough in picking the best variety... and then I waited, and waited, and waited. From reading older threads on the forum here, I can see now that there are many people that have had problems with Arapaho just "not growing" after being planted, so my problem is not unique. Why? I don't know. Maybe the UofA thornless plants have more temperamental soil or climate requirements than the other thornless varieties. I read one article last night about experiments growing commercial varietes in Arizona, and the worst performing of the lot were the UofA varieties. The Texas developed varieties performed very well. Key quote: "Most of the blackberries planted had new shoot growth three to four weeks after planting. Up to three plants of each variety did not have a growth flush; these plants had all died by summer 1994. All the plants of the 'Arapaho', 'Cherokee' and 'Shawnee' cultivars had died by spring 1995. All the plants of 'Cheyenne', 'Choctaw' and 'Navajo' cultivars had died by spring 1997. We attribute the mortality to lack of chilling. Arkansas varieties apparently do not grow well in southern Arizona because of the warm winters, as suggested by Moore (1984)." Arizona article (Dr. Moore is the man behind the whole UofA breeding program for the past 40 years.) I guess I made a mistake going with Arapaho. Such a shame, though, to have to find out this way. Three years wasted. It looks, now, as though I would have been better off with semi-erect thornless varieties (like Triple Crown) that were developed at Maryland. Does anybody have any leads on chill hour requirements? It would be nice if we could make a table.

Unfortunately, the same blackberry plant can have both pink and white flowers, so that's probably not an identifying attribute. Other attributes to consider: (1) thorny / thornless, (2) erect vs semi-erect (e.g. somewhat trailing), (3) timing of blooms and fruit ripening, (4) formation of the flower cluster, and (5) shape and size of fruit. Let us know what you find out.

Water less if water every day that's to much for blackberries water every 3 days at most. In ground when dry water once a week root like some dry time before next watering.

Thanks pinkmountain (great name btw). Probably the real problem is that we have a huge patch of never-tended wild berries and they're just a huge tangle of God knows how many year old dead canes and live canes. We may really end up just cutting them all down and finding a clear patch this winter and burning them - because it's going to be a doozy of a burn pile - and let them start over in a half-way orderly fashion so we can thereafter keep them pruned.