Editor's Note: (Howard G. Buffett is chairman and CEO of the Howard G. Buffett Foundation, which works to improve lives in the world's most impoverished and marginalized communities by investing in food security, conflict mitigation, public safety and efforts to combat human trafficking. He is also a farmer and photographer. The views expressed here are his own. Read more opinion on CNN. )
(CNN) During the fall harvest, across rural America, you may at times encounter a mechanical convoy of combine harvesters rumbling down the road, headed who knows where. As likely as not, the drivers of these huge machines are going to a farm they don't know to harvest a crop they never planted for a farmer they've never met. And they do this without asking for a penny in return.
It's a common act of generosity and solidarity in farm country. The harvest waits for no one, and when a farmer is too sick or injured to bring in a crop, neighbors -- and strangers -- show up to help.
This farmer-to-farmer ethic holds strong across rural America. It's something I think about as I land home in rural, central Illinois after my fourth visit to Ukraine since the start of the war. It's what compels me to extend this generous spirit farther, to help farmers who have been struggling to harvest and plant their fields since Russia's unprovoked invasion in February.
Ukraine is one of the world's great breadbaskets, a vast heartland of wheat, corn, barley and sunflowers. Its simple yellow-and-blue flag is a farmer's flag, evoking golden fields and endless sky. But since the start of the conflict, Ukraine's fields of rich black soil have been trampled by troops, cratered by artillery shells, burned and salted with landmines. For months, its vital Black Sea port was blockaded, keeping critical food aid from hungry countries and wreaking havoc on global food prices and supply. The situation remains perilous. Meanwhile, winter is closing in, many Ukrainian farms and crops have been destroyed, and the conflict shows no sign of ending.
All wars are brutal, but Russian President Vladimir Putin's onslaught has been particularly savage to civilians. Despite Russia's denial of responsibility, each week brings news of more humanitarian atrocities, mass graves and the systematic torture of soldiers and civilians.
Missile and drone attacks on Ukraine's energy infrastructure have left millions without electricity, part of a sustained campaign against civilian targets. Children and the elderly have been slaughtered as Russia's military has aimed its firepower at schools, playgrounds, religious sites, hospitals, residential neighborhoods -- and farms.
I am not a soldier or politician. But as a farmer and philanthropist who has worked on global food-security issues for more than 20 years, I know that when farms are destroyed, the damage spreads far and wide, and recovery is prolonged. People go hungry.
Before the war, Ukraine exported about 6 million to 7 million tons of grain per month, with about 30% going to Europe, 30% to North Africa and 40% to Asia, according to the Ukrainian Grain Association. Much of that grain is desperately needed in places devastated by conflict and drought, like the Horn of Africa. Many of Putin's worst-suffering victims live far beyond Ukraine's borders. Not long ago, in Kyiv, I met a man who owned a farm near Bobrik, a small village about two hours south of the capital. He told me that early in the invasion, Russian forces seized his farm for an operating base. Soldiers moved in and stockpiled ammunition and supplies.
This man gave the coordinates of his farm to the Ukrainian military, so they could bomb the soldiers and munitions occupying it. My new friend had no insurance on his tractors, and no way to replace the fertilizer and other assets he lost. He could have done nothing, but instead he gave up his farm to protect his country. He told me he would do it again if necessary. I heard a version of this story more than once in Ukraine.
No one knows when and how the war will end. When it does, it will take many years for Ukraine to recover. In the meantime, there are things we can do to help.
This is not a distant war that does not affect Americans. The foundation I run has long understood the relationship between food security and conflict. Americans are not insulated from the effects of far-off hunger, instability and violence. We must do everything in our power to keep Ukraine's farms productive and exports flowing. We know that Russians have stolen and sold Ukrainian grain to fund their war machine. They are bent on destroying the agricultural sector so the country can no longer feed the world or itself. These crimes must be stopped and prosecuted.
As Ukrainians courageously stand their ground, we Americans can help. Our foundation supported the first two shipments of grain for food aid through the Black Sea in collaboration with the World Food Programme and the U.S. Agency for International Development. Last summer, we donated thousands of pounds of vegetable seeds to Ukrainian families for home gardens. We are helping farmers clear their fields of mines.
I urge all Americans to summon that farmer-to-farmer ethic and pitch in where they can. On my last two trips to Ukraine, I had the opportunity to run some of the combines we donated, helping bring in the wheat and corn harvest under the blue Ukrainian sky. I know many fellow American farmers would be doing the same if they could.
I've arrived home to a new Congress taking shape, thinking about the bravery and determination of our Ukrainian friends and hoping US leaders, regardless of party affiliation, continue their steadfast support. I'll continue to try to help Ukrainians any way I can and urge all Americans to join me.