צואה יבישה כ"כ שאם יזרקנה תתפרך הרי היא כעפר ומותר לקרות כנגדה והוא שלא יהא בה ריח רע: הגה וי"א דלא הוי כעפר רק אם נפרכת על ידי גלילה בלא זריקה וכן עיקר (רש"י והרא"ש פרק מי שמתו וטור):

The Laws of Dry Excrement, containing 2 s'ifim Excrement which is so dry that if one throws it, it crumbles apart, behold it is like dirt and it is permitted to recite [the Sh'ma] in front of it. And this is if it does not have a bad smell. Rem"a: There are those who say that it is not like dirt unless it crumbles when rolled without throwing it, and such is the correct [opinion] (Rashi and the Rosh on chapter "Mi sheMeito" and Tur)

Urine that was absorbed into the ground - if it [could] moisten the hand, it is forbidden to recite in front of it. Rem"a: And there are those who say that it is not forbidden unless it is moist enough to moisten another thing, which in turn can moisten another thing. And one may rely on this [opinion].