In the hustle and bustle of modern life, man is often too busy to sense God's greatness in the world around him. In this age of mass industrialization, we treat the ground beneath our feet as if it isn't sacred. We no longer feel that it is charged with the grandeur of God. It is just something for treading on, something on which we walk or work.
That's what Hopkins means when he says that "[A]ll is seared with trade; bleared, smeared with toil." Due to this objectification of nature, man no longer recks Christ's rod; that is to say, doesn't heed his divine authority.
And yet, despite man's ignorance, God is ever present. This is his creation and he is always in it, even if we, as unrepentant sinners, fail to recognize his divine presence.