Those leaves are dying because it is the natural end of the plant's life cycle. I would say she is ready. Also after hours and hours of research I don't understand why people want to wait for amber trichs, amber means that the THC has degraded... that's usually a bad thing right? I have smoked a lot of lab-tested medicine in my time and I gotta say, when weed is higher in CBN (What THC degrades into when trichs turn amber) it doesn't correlate to "Couch-lock" at all, it correlates to less potency in all areas (Which makes sense because chemically it is only 10% as psychoactive as THC). Also, recent research has shown pretty conclusively that clear trichomes contain the highest concentration of THC. From a research article on THC content in cannabis (He refers to the three possible colors of trichomes as Translucent, Yellow, and Brown instead of Clear, Cloudy, and Amber, but it refers to the same thing):
"b. Effect of gland age on cannabinoid content
We also examined cannabinoid content of stalked gland by age to measure the major cannabinoid components in both a fiber and drug strain (Table 2). Glands, viewed under a microscope, can be classified according to their secretory phases from the color of their contents.
Glands most active in secretion (mature) are translucent in appearance, aged glands are yellow in appearance and senescent glands are brown in color.
Mature glands possessed the highest content of their major cannabinoid in both the fiber and drug strains. Senescent glands possessed low levels of cannabinoids. The concentration of some components, as CBD in the drug strains, may be so low that is was not detectable in our analysis; similarly, for THC and CBN in the fiber strain. It is unknown where the cannabinoids go during the aging process, but we suggest that it is possible they volatilize into the atmosphere along with the terpenes in glands, as noted later in this report. Nevertheless, this phenomenon of altered content in glands during aging is one that should be studied to gain a more complete understanding of the secretory process of cannabinoids in the cell."
(Mahlberg and Kim,
http://www.hempreport.com/issues/17/malbody17.html)
The rest of the article is worth reading but that is the pertinent section.