Single angled blade coulter and fertilizer opener

Claim 1

In an attachment for a seed planting implement of the type including a main frame adapted to be moved along the ground and having at least one seed planting unit connected to said main frame, said seed planting unit including a subframe and a seed trench forming unit attached to the subframe, the improvement comprising: a single disk blade disposed forward of the seed trench forming unit and mounted to the main frame independently of the subframe, said single disk blade being disposed on a support arm at an angle to the direction of travel of said implement; means for selectively adjusting a downwardly biasing force on said disk blade wherein said adjustable force means includes a compression spring disposed to interconnect a support attached to said main frame and said single disk blade, and a pivotable force adjustment strap pivotally attached to said support and having one end attached to said spring and having the opposite end selectively securable to said support in a plurality of position; and means for selectively adjusting the working depth of said disk blade wherein said depth adjustment means includes a gauge wheel rotatably attached adjacent to said disk blade and having a center point selectively movable with respect to the center point of said disk blade, and wherein said single disk blade is rotatably mounted on a hollow spindle attached to the support arm and said gauge wheel is rotatably attached to an offset spindle of an arm assembly having a first shaft portion received and secured within said hollow spindle.