In article <4aodri$bjq at cmcl2.NYU.EDU>, aqm0521 at is2.nyu.edu says...
>>>We desperately need help for our big cactus (~4 ft. tall).
>>Any help will be greatly appreciated
At any rate you ought to cut off a piece of the healthy plant and repot it
in order to start a new one. They grow easily from cuttings of the lobes.
Or those joints. Be sure to use the proper soil and follow a feeding
program faithfully with cactus fertilizer. Hot sun helps. Good luck
>> Please send responses to alurye at lehman.com.> Thanx
>> Alexander Lurye