Resaca de la Palma
The site called Resaca de la Palma (known as Resaca de Guerrero in Mexico) is a dry river channel, one of many long, water-filled ravines left behind by the shifting course of the Rio Grande. The trace was lined with dense brush and its bed dotted with pools of water--natural features that promised to limit any attack against troops positioned there.
Following his withdrawal from Palo Alto on May 9, 1846, General Mariano Arista occupied this spot, blocking the Point Isabel-Matamoros road crossing with artillery batteries and lining infantry troops along the banks of the resaca in the protective cover of heavy brush. Cavalry troops occupied the rear as a reserve force. Mexican troops hoped to force an infantry battle in the chaparral in place of the open-field artillery duel that been so devastating at Palo Alto.
General Zachary Taylor pursued the Mexican forces from Palo Alto, arriving around 3 p.m. Having left his wagon train safely entrenched at Palo Alto, he was no longer focused on protecting his supplies and immediately ordered a charge on the Mexican positions. As U.S. artillery fired upon Mexican batteries at the resaca crossing, infantry troops rushed into the brush on both sides of the road and engaged Mexican soldiers in furious hand-to-hand combat.
Many of Taylor's soldiers had experience fighting under similar conditions and were well prepared for this fight. The American soldiers also had the good fortune to find a path that led them over the waterway and around the most heavily fortified areas. Once across the resaca they encountered Mexican soldiers with little training in close-quarter fighting, who had not eaten in twenty-four hours, and who were demoralized by the carnage at Palo Alto. Although Mexican forces put up a determined fight, in less than an hour U.S. forces spilled from the brush into the clearing that housed General Arista's field headquarters.
Unaware of the fortunes of his troops in the chaparral, General Taylor ordered Captain Charles May and his Dragoons to seize the Mexican artillery at the resaca crossing. With the support of Captain Randolph Ridgely's artillery, which drew fire to expose the Mexican positions, U.S. horsemen spurred their mounts down the roadway. An initial charge drove many of the Mexican artillerymen from their pieces, but carried May's men well past their target. They then regrouped and retraced their path through a gauntlet of musket fire to capture the Mexican Artillery commander, General Rómulo Díaz de la Vega, and several of his men. Even then fierce fire from Mexican troops forced the 5th and 8th infantry regiments to help take the Mexican cannons.
This determined fight for control of the roadway effectively ended Mexican resistance. With their cannon silenced and U.S. soldiers swarming their camp, disoriented Mexican troops fled for the safety of the Rio Grande. General Arista led a cavalry charge up the roadway, but the U.S. troops advanced in such great numbers that he was forced to join the retreat.
At the close of battle, U.S. troops counted 45 dead and 97 wounded. Mexican forces suffered a reported 158 killed, 228 wounded, including the complete destruction of the Tampico Battalion-whose members faced some of the hottest fire. The Mexican army also counted 168 soldiers missing in action. Many of these were men who succumbed to treacherous currents as they attempted to swim the Rio Grande.
The U.S. victory at Resaca de la Palma ended the Mexican siege of Fort Texas in its sixth day and left the north bank of the lower Rio Grande firmly in U.S. hands. The battle also had an enormous effect on the morale of the two armies. With the official declaration of war still days away, the U.S. troops felt confident that they could defeat their foe at any place and in any numbers. Mexican troops were thrown off-balance by consecutive defeats and would never fully recover.