Hi Gabrielle,
I personally have not climbed any Jackalberry trees. I am aware that their bark is tough and flakey which can be rough on the hands. What I can recommend is that you climb close to the trunk while making sure your climbing rope is over a live branch that is at least 6 inches in diameter. Be sure to use a cambium saver as this will make climbing easier and will cut down on the amount of bark flakes falling into your face and most importantly it helps protect the tree you are climbing.
Jackalberry's can have some nice beautiful spreads where, away from the trunk, the branch structure can become quite weak. Beware when doing switch-overs and/or branch walking.
These trees don't grow very tall but the view from above, I assume, is very rewarding as you'll find most of them in open spaces.
I would be honored to climb and spend some time where the giraffes do some aerial grazing.
What kind of research are you doing?
****Even if you are only going up 4 meters I'd highly recommend using a rope and harness. (Are you a technical climber or a free climber?)
Hope this helps. Please send us a report on your experience and your findings.
Adventure-UP!
Tengu,
Keep-Balance
Tim 'tengu' Kovar