Howdy! I also live in heavy pine woods (second growth, not the healthiest). Me and mine have found that pine wood, sap, needles, its all very acidic, but only when its standing. If you drop pine logs, let em lie a year and intern them, I see no problems outside of the usual nitrogen lockup (slow growth the first year) and as long as you plan accordingly with some early succession plants, youll do fine. Importantly,
Hugelkultur is about making due with what youve got at hand, so Im liable to think any wood that isnt famously hardy will do just fine.
The needles and duff are also great for mulch and soil, but youve gotta chip em or something. It seems like chipped stuff becomes happy, non-acidic soil just fine.(most soil is acidic here, Im only looking for acute increases where I use pine) Ive grown to suspect that the relative allelopathy of Pines is not chemical, but from them dropping cannon(cone-un?)balls before dropping spiny, waterproof needles a foot thick. Pushy Pinus!