There's an excellent trip report from Keeponchuggin from March 1. This report is intended to compliment that one. I was trail running, and I did save a GPX track of my route and will make that available soon.
I'm attaching a diagram to this report showing modifications in the trail, which I'll describe here.
The Ira Spring trail is fine until you get to what's usually the start of the talus slopes beneath the highest point of the Mason Lake hike (aka: "the ridge"). That turn in the trail is indicated by "A" in the diagram. I tried to take the usual hard right there but, the trail essentially ends ~0.15 miles past that point, so I turned back.
In the meantime, some intrepid hikers created a bootpath over the rocks from point A to the ridge. That's "B" on my diagram. It's short, but IMO tricky and dangerous, because you're postholing between large rocks, which is never a good look.
(The summer trail / aka: "normal trail" is indicted via a dashed purple line.)
Getting to Mason Lake from there is do-able. Microspikes are a requisite from perhaps 0.2 miles before point A. There's ~3'-4' of snow in and around the Mason Lake basin, making for some slow going. The lake itself is buried under snow.
Once you pass Mason Lake, you'll come to the T junction (L = Defiance / R = Island), go left and follow the usual trail towards Defiance.
Approx ~0.33-0.4 miles past that T, you'll see a bootpath that deviates from the usual trail. This is point C on my diagram. From there it's a straight shot up the SE ridge of Defiance. It's quite steep at times, and the snow is wicked deep. I postholed up to my waist several times, which was disconcerting. It does join up with the usual trail as you near the section where you emerge from the trees and out onto the open slopes beneath the summit.
I stopped because conditions were difficult (it was foggy and snowing heavily), but I assume if I wanted to scramble my way up there, I could have continued on. I stopped at 5,128'. It was peaceful and lovely up there, as I had the place to myself.

Comments
Great workout!! I think my team created boot path from A to B if you see the WTA report on 2/27. We were going to plan to go to the Sir Richard's pond, but we stopped at the Mason Lake and came down via Old Mason Lake trail that day.
Posted by:
Chong Lee on Mar 04, 2025 08:57 PM
Great workout!! I think my team created boot path from A to B if you see the WTA report on 2/27. We were going to plan to go to the Sir Richard's pond, but we stopped at the Mason Lake and came down via Old Mason Lake trail that day.
Posted by:
Chong Lee on Mar 04, 2025 09:01 PM