grow a chrismastree

I don't see any information on the nutes you are giving her but the tips are indicating nute burn. Since she's in flower, you need to reduce the amount of grow nutes you're giving and definitely (if you aren't already) give her some bloom nutes and a dose of calmag (1tsp/gal once a week only). You're lucky in that you don't have a calcium deficiency as yet so that's terribly good! In week 3 of flower, plan on giving her a good PK boost from then on through harvest and you'll be very pleased with your harvest (you should be pleased anyway!) Good luck....