Early-Installment Weirdness: Dr. Baker has somewhat of an accent, while Mrs. Oleson is a much darker, haughtier woman than the comic foil the character would later become, and Reverend Alden is far more stern and serious than the warm-hearted preacher he'd be known as in the series. Also, since this IS the first episode, a good deal of the episode is spent introducing us to everyone and the Ingalls getting to know the townsfolk that would soon become their neighbors and closest friends.
Ironic Echo: When Charles insists on working on their soil on weekends and even skips Sunday church as a result, Caroline calls him out, and he responds that God's not gonna finish the job for them. When he's injured and can't finish the plowing and Caroline fills in for him, he protests against her to which she responds with the exact same words. He resigns with a chuckle.
Nice Job Fixing It, Villain: O'Neil taking the oxen a day before the time is due forces Charles to get up his bed despite his injuries, and try to finish the job in front of the other townspeople who, upon witnessing his and his daughters' determination to keep the deal, join to help him finish it. Had O'Neil collected the oxen after the deadline, he'd have won and the Ingalls would have lost their oxen.
Title Drop: In the end, after the townspeople help Charles finish his job and keep his oxen, Laura's voiceover informar that her Pa was glad they came to Walnut Grove, because he realized they harvested a crop he didn't know they'd reaped: A Harvest of Friends.
O'Neil when he takes the oxen after Charles is injured and rendered unable to complete the job in exchange for the seed sacks, as part of their deal. He even seems to express some remorse after Charles tries and fails to finish the job in his bad state, and then his daughters try to finish it before the deadline. However, he could have extended the time for Charles and chose not to, and when the townspeople help the Ingalls finish the job and he tries to explain himself, they don't buy it and just give him the cold shoulder.
Mrs. Oleson is introduced as an obstructive, haughty character, but her refusal to not sell the Ingalls anything on credit, as they are newcomers and there have been examples of farmers who didn't keep up with their debts, is perfectly justified, though her attitude is still rude.
Vitriolic Best Buds: Dr. Baker and Lars Hanson have their dynamic as bickering friends introduced here.
Welcome Episode: The first episode of the series proper shows the Ingalls building their iconic home on the banks of Plum Creek, just outside of Walnut Grove, and time is spent getting introduced to the characters and their basic traits.
What Happened to the Mouse?: O'Neil is never seen again after this episode. It's implied that he realized that he'd no longer be welcome in Walnut Grove and chose to move from there.
