The city's commemoration of the tornado that devastated north Minneapolis exactly one year ago began today with the planting of a tree in the yard of Jan Carstens, whose husband Rob MacIntyre was one of two people killed in the storm.Mayor R.T. Rybak and other public officials gathered this morning to honor MacIntyre's memory before planting a black hills spruce on the front lawn.The mayor said the planting of the tree is "one more step toward the rebuilding of north Minneapolis," where the city will plant hundreds more in the fall to fill the empty spaces where trees were destroyed in the storm.In a few years when people return to mark the anniversary of the tornado, they will "come here not just to see and think about the devastation but also to see flowering trees that remind us that even in the toughest of times, hope does bloom," Rybak said.MacIntyre, 53, died while trying to help a neighbor clean up after the storm.Carstens and several neighbors were also present during the ceremony, during which the mayor called for a minute of silence.Council Member Don Samuels praised MacIntyre for his kindness, saying, "It's truly right that he should die in an act of generosity because that's how he lived."Susan Gethin, CEO of the nonprofit Tree Trust, said the spruce was a symbol.It represents "hope and optimism for a positive future for north Minneapolis," she said.Several citizens on Facebook questioned the event after the city posted details."A single tree? That's it?" asked one resident.Posted another: "Trees are nice, but a lot of us on the North Side are tired of 'symbolic gestures' and would appreciate the same type of attention and investment that other parts of the city get."The city says that more than 3,000 trees are being planted by the parks board around the North Side this spring.At 2:30 today, Rybak will also join students, staff, and others in a peace circle on the field at Lucy Laney School to release balloons. Then they'll go on a bike ride to the University of Minnesota Urban Research and Outreach-Engagement Center.Rybak will speak at the center at 3:45, in an event also to be attended by Samuels, Council Member Diane Hofstede and Council President Barbara Johnson.