Nuevamente pongo mi codigo con el que pude recortar la imagen
Espero a alguien le sirva
Código [Seleccionar]
Dim bmpdest As Bitmap
Dim lienzo As Graphics
Dim x, y As Integer
Dim rect, rect1 As Rectangle
bmpdest = PictureBox1.Image
lienzo = Graphics.FromImage(bmpdest)
x = bmpdest.Width
y = bmpdest.Height
rect = New Rectangle(0, 0, x, y)
rect1 = New Rectangle(0, 370, 3500, 1800)
lienzo.DrawImage(PictureBox1.Image, rect, rect1, GraphicsUnit.Pixel)
PictureBox2.Image = bmpdest
Espero a alguien le sirva