Burn decks are very finely tuned around their cards doing just enough damage to count up to 20. Being able to turn their Bolts into Shocks is extremely valuable. In addition gumming up the board requiring them to point burn spells at the spellskite means more time and less resources on the burn player's side. Spellskite also has the added luxury of being a near free roll against infect and twin. Boil doesn't seem all that great since you'll be hard pressed to resolve it against a competent twin player not to mention twin has a decent amount of non-island lands to play around it as well. Consider instead, Thrun against slow blue based control decks and maybe illness in the ranks or Night of Souls' Betrayal against twin/infect. Rakdos charm seems a bit too 'cute' in my opinion: Grudge is better at killing artifacts; instant speed gaveyard removal isn't all too amazing in the current meta, would much rather have a bojuka bog or Relic; the last mode only really works once against a twin player and only if you have more life than they do. double that amount if they use pestermite.
In general it seems like the JUND versions just have a harder time against burn than the NAYA or RUG variants of Loam.
Try using the Scar's fast lands instead of the polluted deltas; that should help with the life loss. Maybe try Kitchen Finks as well to provide a life buffer as well as semi-combo with Smallpox.
Trying out Resolute Archangel for the burn MU since it dodges skullcrack and the new RG command. Not entirely sold on the 3 Blood Moons; might try out Fulminator Mage if I can get any. Swapped out Noble Hierarchs for Birds since the inability to produce red mana was starting to have slight issues.
Yeah the leylines are there purely for the storm and burn match ups. I was considering Kitchen Finks over the Courser; however I don't feel like a 1 of kitchen finks is worth and I'm not sure what else I would cut to add more. Completely forgot about bojuka bog and sejiri steppe; thanks for the tip. Honestly if Wizards would just reprint the cycle lands Loam would be so much stronger.
And @Lord Hazanko: There are definitely options such as abrupt decay and murderous cut for the BGx versions; Also Sigarda is actually impossible for Jund/Junk to remove once resolved. I think post board you just have to accept that Junk has way to many ways to interrupt the loam strategy and move to something else.
Another take on Assault Loam. Unburial rites on Elesh Norn mb helps against aggro decks and g2 Iona on red is the main way to deal with the Burn MU. Much weaker to storm if anyone still plays that though. Sideboard is a bunch of random cards past the Iona and Terastodon.