by John Bush 　　The high point of Willie Colón's ongoing collaboration with Rubén Blades (and close to a career peak for both artists), Siembra exploded on the salsa scene in 1978 and has never been forgotten by fans. Beginning with a minute of playfully deceptive quasi-disco arrangements, Colón and his band slip into a devastating salsa groove for the opener, "Plástico," on which Blades first criticizes America's throwaway society and then brings all of Latin America together with a call to unity. Blades wrote all but one of the songs on Siembra, and shines on all of them; his extended high-tenor salsa scatting lifts "Buscando Guayaba," his tender side comes across on the love song "Dime," and he outlines a devastating life-in-el-Barrio exposé with "Pedro Navaja" (Peter the Knife). For the latter, Colón and Luis Ortiz's tight arrangement adds immeasurably to the song, using street noise and sirens, breaking into an ironic "I like to live in America!," and punching the statement home with a four-trombone line. Reflecting the tough times but optimistic attitude of el Barrio during the late '70s, Siembra joined Cosa Nuestra as one of Willie Colón's career landmarks.