Aesc is the dipthong “ae”
Anglo-Saxon Rune Poem (from ragweedforge.com)
The ash is exceedingly high and precious to men.
With its sturdy trunk it offers a stubborn resistance,though attacked by many a man
My sense of Aesc is that it relates to the powers of the Upper World. The Aesir, Alfar, and the Vanir (at least, the spring/summer faces of the Vanir) and many other spiritual beings that could be identified as being Upper World, celestial, heavenly, or Astral (in the sense that Astral refers to the stars). It also connects to Ond/Azoth/Quintessence/Aether, the substance that underlies all other substance, the essence that weaves the worlds together, that is precious, but also enduring. When it is reversed, it shows the descent of those powers and forces, pouring forth into the worlds below, bring about change, inspiration, and opening up the passages, both internal and external, to the Worlds Above. It was strongly confirmed this Thursday, as a working I have been doing for the past 9 months came to a sudden and pronounced completion