Remove the strings from the snap peas. Trim the woody ends off the asparagus. Peel the turnips and carrots.
Cut all of the vegetables into 2″-3″ long and approx. ½″ wide fingers.
Heat the oil and ½ tbsp. butter in a very large sauté pan over medium-high heat. When the oil begins to shimmer, add the carrots. Cook for 2 minutes, tossing them in the pan occasionally.
Add the remaining vegetables, starting with turnips, followed by asparagus and snap peas, and finally scallions. Cook for 1 minute between each addition. The vegetables should be crisp-tender.
Add garlic and salt and pepper to taste and toss to combine. When the garlic is fragrant (30 seconds), remove the veggies from the pan.
Using the same hot pan, combine the remaining 1½ tbsp. butter with white wine and lemon. Stir regularly over medium heat, until the wine reduces by half.
Pour the sauce over the veggies and turn to coat.
Serve warm.