A noun in The Etymologies of the 1930s glossed “poplar-tree”, cognate to ᴹQ. tyulusse, both derived from the root ᴹ√TYUL “stand up (straight)” (Ety/TYUL).
Conceptual Development: Earlier words for a poplar tree include G. cwithwiros “poplar” in the Gnomish Lexicon of the 1910s based on G. cwitha- “murmur” (GL/29) and ᴱN. {aigir >> lalath >>} loloth “poplar-tree” in Early Noldorin Word-lists of the 1920s (PE13/136, 149).
In Tolkien’s later writings he decided that initial palatized dentals like ty- were no longer a feature of Primitive Elvish, and he revised other derivatives of the root ᴹ√TYUL to use kyul- instead, most notably ✶kyul(u)mā > Q. tyulma “mast” (SD/419; PE21/74, 80).
Neo-Sindarin: I ignore this particular change for purposes of Neo-Eldarin as it requires us to abandon too many words; see the entry on how [[at|[j] was lost after initial dentals]] for further discussion. As such, I would retain tulus “poplar-tree” for purposes of Neo-Sindarin. If, however, you want to follow the later paradigm, you should adopt this Noldorin word as ᴺS. ✱culus “poplar-tree”.
A noun from The Etymologies of the 1930s glossed “support, prop” derived from ON. tulugme < ᴹ✶tulukmē under the root ᴹ√TULUK (Ety/TULUK).
Conceptual Development: Earlier words of similar meaning include G. talp “prop or support” from the Gnomish Lexicon of the 1910s based on the early root ᴱ√tlp (GL/69) and ᴱN. taichr “prop, support” from Early Noldorin Word-lists of the 1920s derived from primitive ᴱ✶tank’rú (PE13/153). An earlier word of similar derivation was G. taul {“burden” >>} “a pillar” related to G. tul- “†to support” (GL/69).